2014 insurgency in Donetsk and Luhansk

Since the beginning of March 2014, demonstrations by pro-Russian and anti-government groups have taken place in the Donetsk and Luhansk oblasts of Ukraine, in the aftermath of the 2014 Ukrainian revolution and the Euromaidan movement. These demonstrations, part of a wider group of concurrent pro-Russian protests across southern and eastern Ukraine, have since escalated into an armed standoff between the separatist forces of the Donetsk and Lugansk People's Republics, and the Ukrainian government in Kiev.

Donetsk Oblast
Attempts to seize the Donetsk Regional State Administration (RSA) building occured since pro-Russian protests began in the eastern and southern regions of Ukraine in the wake of the 2014 Ukrainian revolution. Pro-Russian protesters occupied the Donetsk RSA from 1 to 6 March, before being removed by the Security Service of Ukraine. On Sunday, 6 April, 1,000–2,000 protesters attended a rally in Donetsk pushing for a referendum on independence from Ukraine. The protestors then stormed and took control of the first two floors of the building demanding that if an extraordinary session was not held by officials, announcing a referendum to join Russia, they would declare unilateral control by forming a "People's Mandate" and dismiss all elected council members and MPs. The protestors voted in favour of independence and proclaimed the Donetsk People's Republic.

Luhansk Oblast
Unrest in Luhansk Oblast began on 6 April, when approximately 1,000 activists seized and occupied the SBU building in the city of Luhansk, following similar occupations in the cities of Donetsk and Kharkiv. Protestors barricaded the building and demanded that all arrested seperatist leaders be released. Police force was able to retake control of the building, but locals gathered for a 'people's assembly' and called for a 'people's government', demanding either federalisation or incorporation into the Russian Federation. Activists elected Valery Bolotov to the position of "People's Governor". Two referendums were announced, one on 11 May to decide if the region should have autonomy or retain its current constitutional arrangement and a second scheduled for 18 May to decide whether the region should join the Russian Federation or become completely independent.

The Lugansk People's Republic was declared on 27 April. Representatives of the Republic demanded that Ukrainian government provide amnesty for all protesters, enshrine Russian as an official language, and hold a referendum on the status of the region. They issued an ultimatum that stated that if Kiev did not meet their demands by 14:00 on 29 April, they would launch an insurgency in tandem with that of the Donetsk People's Republic.

History
After having gained control of the Donetsk RSA and declaring the Donetsk People's Republic, pro-Russian groups vowed to fan out and take control of strategic infrastructure across the oblast, and demanded that public officials who wished to continue their work to switch allegiances. By 14 April, pro-Russian separatists had taken control of government buildings in many other cities within the oblast, including Mariupol, Horlivka, Sloviansk, Kramatorsk, Yenakiieve, Makiivka, Druzhkivka, and Zhdanivka.

First standoff
In response to the widening unrest, acting Ukrainian President Oleksandr Turchynov vowed to launch a major counter-terrorism operation against separatist movements in Donetsk Oblast. Ukrainian acting Interior Minister Arsen Avakov declared on 9 April that the unrest in Donetsk Oblast would be resolved within forty-eight hours, either through negotiations or the use of force. President Olexander Turchynov signed a decree to retake the Donetsk RSA building, and place it "under state protection," and offered amnesty to the demonstrators if they lay down their arms and surrender.

Expansion of territorial control
On 12 April, unmarked seperratist soldiers seized the Interior Ministry office in Donetsk without resistance. Following negotiations with those in the building, the head of the Donetsk Ministry of Internal Affairs resigned. Former Berkut officers, who had been dissolved by the government following their actions during the February revolution, took part in the raid and sided with the separatists. On 16 April, Donetsk City Hall was stormed by insurgents. Further protests saw the capture of the regional state television network on 27 April, which succeeded in resuming some Russian-language broadcasts that had been banned in the aftermath of the Russian annexation of Crimea. On 4 May, police raised the flag of the Donetsk Republic over the Donetsk police station.

Sloviansk
On 12 April armed men took control of the city council, the police department and SBU buildings in Sloviansk, a city in the northern part of the Donetsk Oblast. The occupiers raided the police weapons cache seizing hundreds of firearms, which prompted the Ukrainian government to launch a counter-terrorism operation to retake control of the city. The counter-terrorism operation began the following morning on 13 April. Insurgents removed the former mayor, Ms Nelya Shtepa who was replaced by self-proclaimed "people's mayor" Vyacheslav Ponomarev, who in turn was himself removed on 10 June 2014. As of 18 June the town was still under siege by the Ukrainian Army and it has been estimated that 15-20,000 refugees have fled the city.

Kramatorsk
In Kramatorsk, northern Donetsk region, a shootout with police occurred as the separatists attacked the police station before capturing it. Donbass Militia members tore off the sign of the station and raised the flag of the Donetsk Republic. The gunmen then gave an ultimatum that if by Monday the city's mayor and his subordinates did not side with the Republic, then they would "take the executive committee;" a crowd of separatists rallied around the executive committee building and flew the Republican flag from the top of the building. Other activists had already entered the city council building. A Donetsk Republic representative addressed locals outside the police station, and was received negatively with booing.

After an offensive on 2–3 May that routed insurgents from the SBU building, Ukrainian troops withdrew from the city on 4 May.

Horlivka
On 12 April, in Horlivka, men attempted to seize the police department but were stopped. The purpose of the raid was an attempt to seize weapons, police said. Police stated they would use firearms to defend against "criminals and terrorists."

However, on 14 April, after a tense standoff, the regional police headquarters in Horlivka was successfully stormed by activists. Some members of the local police unit defected to the People's Republic earlier in the day, while the remaining officers eventually retreated, allowing the pro-Russian forces to take control and raise the flag of the People's Republic over the building. The chief of police was captured, beaten, and hospitalised. On 17 April, city council deputy Volodymyr Rybak was kidnapped by masked men; on 22 April, a body was found in the river believed to be his. Pro-Russian protesters seized the city council building and Horlivka police division on 30 April.

Mariupol
On 13 April, pro-Russian people took administration in Mariupol. However, on 24 April, the city administration in Mariupol was allegedly "liberated", but was denied by Pro-Russian protesters who were seen at the building.

Clashes escalated in early May, when the city hall was retaken by the National Guard, but then was taken back by Pro-Russians. When militants launched an attack on the police station, Ukraine responded by sending in troops, but were unsuccessful in forcing them out.

Things changed, however on 16 May when steelworkers routed insurgents and militants from the city hall and other buildings in Mariupol, and most insurgents left and the ones remaining were unarmed. However, the Donetsk People's Republic HQ still remained untouched and demonstrators could be seen outside the burnt city hall.

Eventually, on 13 June, all of the city was retaken by Ukrainian troops, alongside the National Guard. The HQ of the Donetsk People's Republic was taken over, and Mariupol was declared the provisional capital of the Donetsk Oblast while the Flag of Ukraine was raised on the city hall.

Druzhkivka
In Druzhkivka, pro-Russian militants reportedly seized the district administration.

Krasny Liman
On April 12, police repelled an attack on the police station in Krasny Liman, but the building was eventually taken over.

In June, heavy fighting broke out in the city, which resulted in the town being shelled by the Ukrainian Army. Ukrainian forces retook the city, and the Ukrainian flag was seen flying on the city hall.

Heavy fighting broke out in June 19, in which pro-Russian militants suffered heavy losses, and retreated from towns near the city. On June 20, independent media reports indicated that possibly 4000 pro-Russian militants had been cut off from Sloviansk and were urgently requesting intervention by Moscow. Approximately 200 pro-Russian soldiers were reported killed with hundreds more wounded.

Other cities
On 12 April, Ukraine's Interior Ministry denied that Krasnyi Lyman, Kramatorsk, and Krasnoarmiisk's government buildings had fallen to separatists. However, on 16 April protesters hoisted the flag of the Donetsk People's Republic over city administration buildings in Krasnoarmiisk and Novoazovsk.

In Artemivsk, separatists failed to capture the police station but entered the city council building and raised the flag of the Donetsk Republic from the roof of the building.

Donbass People's Militia members took the regional council building in Khartsyzk.

On 14 April, pro-Russia activists seized the local council building in Zhdanovka and declared loyalty to the People's Republic.

On 18 April, pro-Russian activists took over the local administration and police buildings in the city of Seversk. Local law-enforcement authorities subsequently announced that they would co-operate with the pro-Russian activists.

On 20 April, separatists in Yenakiieve, who had occupied the city council since 13 April, left.

On 24 April, 70-100 insurgents armed with assault rifles and rocket launchers attacked a weapons depot in Artemivsk, Donetsk Oblast, which housed up to 30 tanks. They were met with resistance from Ukrainian military and retreated. A substantial number were wounded from the insurgents, along with one Ukrainian soldier as well. Avakov said the group was led by a man with "an extensive beard," hinting at Russian militant Alexander Mozhaev.

Up to 30 pro-Russian gunmen seized the police headquarters of Konstantinovka on 28 April. Previously, on 22 April, a local newspaper that was critical of the People's Republic had its office in Konstantinovka burned down by pro-Russian protesters.

Government counteroffensive
According to German media, FBI and CIA agents advise Ukrainian government on ending the rebellion in the east of Ukraine.

In response to the actions, acting Ukrainian President Oleksandr Turchynov vowed to launch a major counter-terrorism operation against separatist movements in the country's eastern regions. Later that day on 7 April, the SBU office in Donetsk was retaken by SBU Alpha Group. Russian media claims that, Alfa Special unit from Donetsk refused orders from Kiev, explaining it by the fact that their duties are counter-terrorism actions.

Ukrainian acting Interior Minister Arsen Avakov announced on 9 April that the separatist protests in Ukraine's eastern region would be resolved within 48 hours – either through negotiations or the use of force. "There are two opposite ways for resolving this conflict -- a political dialogue and the heavy-handed approach. We are ready for both," he said, according to official news agency Ukrinform. Acting President Olexander Turchynov has already signed a decree to take the Donetsk Regional State Administration "under state protection," and has offered amnesty to the separatists if they lay down their arms and surrender. On the 11th, Prime Minister Yatsenyuk said he was against the use of law enforcement scenarios, "but there is a limit."

On 15 April, Kiev announced to launch a counteroffensive against Pro-Russian Protesters. The correspondents did not hear or see any fights in the morning. Ukrainian troops re-took the airfield in Kramatorsk after a gunfight with the people's militia which resulted in at least four deaths.

After the Ukrainian army re-took the airfield, the commanding general of the unit, Vasily Krutov, was surrounded by hostile protesters, who demanded to know why the Ukrainian troops had fired upon locals earlier. Krutov was eventually dragged back to the airbase and, along with his unit, were blockaded by protesters who vowed not to let the troops leave their base. Krutov later told reporters that "if they (separatists) do not lay down their arms, they will be destroyed."

The People's Militia entered Sloviansk on 16 April with six armoured personnel carriers they claimed to have obtained from part's of the 25th Airborne Brigade who had surrendered their arms in the city of Kramatorsk. Reports say the occupants were disarmed after the vehicles were blockaded by locals. In another incident, several hundred residents of Pchyolkino, south of Sloviansk, surrounded another column of 14 Ukrainian armoured vehicles. After negotiations, the troops were allowed to drive their vehicles away, but only after agreeing to surrender the magazines from their assault rifles. These incidents apparently led President Turchynov to disestablish the 25th Airborne Brigade. Three members of the people's militia were killed, eleven were wounded, and 63 arrested after an attempted storming of the National Guard base in Mariupol was repulsed.

According to BBC's David Stern on 17 April, "Ukraine's 'anti-terrorist' operation is looking more and more a non-event, or worse, an outright fiasco." Some Ukrainian soldiers refused "to shoot at their own people" and the offensive is losing its momentum.

On 22 April, Ukraine's acting president relaunched military operations against pro-Russian militants in the east after two men, one a local politician, were found "tortured to death". The politician, Volodymyr Rybak, was found near Sloviansk and had been abducted by pro-Russian "terrorists." "The terrorists who effectively took the whole Donetsk region hostage have now gone too far," he said.

According to the Ukraine Interior Ministry, the city of Sviatogorsk, near Sloviansk, was retaken by Ukraine on 23 April. The Ministry of Defense later announced it had taken control over all important facilities in the Kramatorsk area.

Ukrainian Interior Minister Arsen Avakov announced on 24 April that Ukrainian government forces had liberated the city hall in Mariupol after a clash with pro-Russian protesters there. However, Natalia Antelava of the BBC, said that while it appears that although the mayor and an armed contingent did enter the building early in the morning, there was later no sign of Ukrainian troops at the city hall. Pro-Russian activists blamed Ukrainian nationalists for the attack but said the separatist movement was now back in charge. "We, the People's Republic of Donetsk, still control the building. There was an attempted provocation but now it's over," Irina Voropoyeva, a representative of the People's Republic, told Reuters on 24 April.

Ukrainian officials alleged that the counter-insurgency operation intended to retake the all of Sloviansk on this day, but an increased threat of a Russian invasion halted the operation - Russian forces mobilised to within 10 km of the Ukrainian border. The government confirmed 7 were killed during the operation. President Turchynov later addressed the media, announcing the 'anti-terrorist' operation would be resumed, citing the ongoing hostage crisis.

As of 6 May, 14 servicemen died and 66 were injured as part of the counteroffensive.

On early 7 May, the Ukrainian National Guard retook the city hall in Mariupol after heavy fighting with pro-Russian militants overnight. Anti-Kiev protesters claimed that the National Guard used a toxic gas during the operation, resulting in injuries when anti-Kiev protesters attempted to re-occupy the building later on 7 May after the National Guard had withdrawn. By the end of 7 May, the flag of the People's Republic was flying over the building.

On 9 May, Ukrainian security forces attacked the police headquarters in Mariupol in an attempt to recapture it from militants. During the assault, the attacking forces set fire to the building in a bid to drive out the rebels. The Ukrainian Interior Minister claimed it was the militants, 60 of them, who attacked the police station and the police managed to repulse the assault. 6–20 militants were killed along with one police officer. Four militants were captured and five policemen were wounded. One armoured personnel carrier was captured by pro-Russian protesters and after the clashes they built barricades in the city center. At the same time, Ukrainian National News claimed separatists attempted to disarm Ukrainian troops near Donetsk. The troops resisted firing warning shots and arresting 100 separatists. Also, an Ukrainian Orthodox Church (Moscow Patriarchate) priest attempted to negotiate with the separatists near Druzhkivka but was shot 8 times and killed, which was confirmed by the Church and Prosecutor's Office.

Hostage crisis
During the crisis, at least a dozen individuals, including journalists, city officials, local politicians, and members of the Organization for Security and Cooperation in Europe (OSCE) have been taken hostage by Donetsk Republic separatists across the region. Two abductees have been murdered by pro-Russian forces. Sloviansk has held the highest concentration of hostages, with Republic city mayor Vyacheslav Ponomarev claiming to hold at least 10; vowing to take more as bargaining chips, and to execute them in the result of a government counter-assault. On 25 April 13 more were taken hostage, including 8 OSCE members. These hostages were later released on 3 May.

On 9 May at 19:00 militants in Donetsk raided the city's Red Cross office, capturing large stocks of medical supplies and detaining 7-9 male Red Cross workers (female workers present were released). The prisoners were accused of espionage, and held in the Donetsk Regional State Administration building, until they were released at 02:00 on 10 May. One of the prisoners had been severely beaten.

Post-referendums
It was reported on 12 May that, following the local autonomy referendum, Donbass People's Militia leader Igor Girkin (known as "Strelkov") declared himself "Supreme Commander" of the Donetsk People's Republic. In his decree, he demanded all military stationed in the region swear an oath of allegiance to him within 48 hours, and all remaining Ukrainian military will be "destroyed on the spot." He then petitioned the Russian Federation for military support to protect against "the threat of intervention by NATO" and "genocide."

On 15 May, self-declared governor Pavel Gubarev instituted martial law and threatened "total annihilation" of Ukrainian armed forces if they did not pull out of the Donbass region by 9pm local time. "There remains one hour for the Ukrainian invaders to fulfill the terms of the ultimatum - to remove the illegal checkpoints and pull their troops and weapons away from the cities of Donbas. Otherwise there will be total annihilation of everyone - both the weapons and the personnel of the fascists!" Gubarev said on Facebook. The threat was confirmed by Republican co-leader Myroslav Rudenko. Separately, an ultimatum issued by Sergei Zdrilyuk, a self-styled separatist commander in Donetsk, issued an ultimatum set to expire sometime on 16 May. In his statement he claimed: “I will have enough manpower and resources, and my commander gave me his support in this matter, for all of this to be destroyed and burnt down.” In five cities in Donetsk oblast, thousands of Metinvest steelworkers under the employ of oligarch Rinat Akhmetov established control over Mariupol and, according to Andrew E. Kramer of The New York Times, "routed the pro-Kremlin militants, while also establishing a presence in Donetsk itself." The steelworkers used industrial trucks and equipment from their factories to dismantle all the barricades that had been erected. The workers, who were joined by police, said they were "outside politics" and just trying to establish order. Metinvest executives claim 18,000 workers signed up for the voluntary patrols'', by Andrew E Kramer, 15 May 2014.

However, according to a report by CNN on 19 May, it was unclear who controlled Mariupol, as militia of the People's Republic were still patrolling the city center and holding rallies to commemorate the dead from the 9 May clashes in the city. Denis Kuzmenko, the self-declared local leader of the Donetsk People's Republic in Mariupol, denied that the steelworkers of Metinvest were opposed to the People's Republic, "[the steelworkers] are patrolling because they support the Donetsk People's Republic and they want order."

On 17 May Girkin (Strelkov) issued a video address in which he expressed disappointment with the lack of local support and recruits, that the fighting corps of the Donbass Militia was primarily men over the age of 40, and encouraged women to enlist to fill the deficit.

Donetsk-based steel magnate Rinat Akhmetov called on his 300,000 employees within the region to "rally against separatists" on 20 May 2014. Sirens sounded at noon at the factories to signal the beginning of the rally. In Mariupol it was largely ignored by the workers, who continued on with their jobs. A so-called Peace March was held in the stadium Donbass Arena in Donetsk accompanied by cars beeping their horns at noon. BBC News and Ukrayinska Pravda reported that some vehicles were attacked by separatists and that armed gunmen had threatened (at) the offices of several city taxi services not to take part. In response to this all, and Akhmetov's refusal to pay taxes to the organisation, on 20 May self-declared Chairman of the Council Denis Pushilin announced the Donetsk People's Republic would attempt to nationalise Akhmetov's assets. On 25 May, between 2,000 to 5,000 protesters marched to Akhmetov's mansion in Donetsk city and demanded the nationalisation of Akhmetov's property, while chanting "Akhmetov is an enemy of the people!". According to the Russian-state news agency ITAR-TASS, Akhmetov was believed to be in London during the protests.

On 22 May, 18 Ukrainian soldiers were killed when armed separatists attacked a Ukrainian army checkpoint in the village of Blahodatne, north of Volnovakha. Three armoured personnel carriers and several trucks were also destroyed in the attack and one rebel was killed in the raid.

Also on 22 May, a convoy consisting of 100 government troops attempted to cross a bridge at Rubizhne, near Luhansk, and advance into rebel-held territory, but they were ambushed by a group of 300–500 rebels. After fighting that lasted throughout the day, the military retreated. 2–14 soldiers and 7–20 militiamen were killed during the day's fighting. Three army infantry combat vehicles and one truck were destroyed and another three armoured vehicles were captured by the rebels.

The same day, the Interior Ministry of Ukraine said that the separatists had attempted to enter Luhansk from Russia, but were repelled by border guards. Also, the leader of the separatist movement in Luhansk, Valery Bolotov, declared martial law in the region.

Also on 22 May, the separatists established the political party "New Russia" led by Pavel Gubarev. He announced territorial expansion to Kharkiv, Kherson, Dnipropetrovsk, Mykolaiv and Zaporizhia "Once we solve the problem of Sloviansk," and the foundation of a new self-declared confederate state. The state would, according to Aleksandr Dugin, have its capital in Donetsk, Russian Orthodoxy Christianity as the state religion, and nationalise major industries.

The next day, a unit of the Ukrainian Donbas Volunteer Battalion attempted to advance on rebel positions at a separatist checkpoint near the village of Karlivka, northwest of Donetsk. However, they were ambushed by a group of 150-200 separatists, backed-up by an armoured personnel carrier, leaving five of the pro-Ukrainian fighters dead, according to the Healthcare ministry, as well as four separatists, per an AFP photographer. 20 pro-Ukrainian soldiers were also wounded and at least four captured. The volunteer battalion was surrounded by the separatists and outnumbered 6-1 until fighters from the nationalist Right Sector allegedly broke through the encirclement to allow the core of the Donbas Battalion to escape. The involvement of Right Sector was disputed by the Donbas Battalion command. Pro-Russian leader Igor Bezler claimed he executed all of the captured soldiers. A rebel leader confirmed four of their fighters were killed, but also claimed that 10 soldiers and two civilians also died. Other sources confirmed only one civilian death. Also during the day, two pro-Russian separatists were killed during a raid on a local government building they had been occupying in Torez by members of the paramilitary Ukraine Battalion led by Oleh Lyashko.

Airport battle and fighting in Luhansk
During the morning on 26 May, 200 pro-Russian rebels, many of the Vostok Battalion, captured the terminal area of Donetsk International Airport and demanded the withdrawal of government patrols. The militants also blocked off the road to the airport. Soon after, the Ukrainian National Guard issued an ultimatum to the separatists to surrender, which was rejected. Following this, paratroopers launched an assault and an air strike was also conducted against the rebels. Attack helicopters were also used which targeted a rebel anti-aircraft gun. As evening fell, the situation was unclear with the military pushing out the rebels. Donetsk Mayor Oleskandr Lukyanchenko said the death toll in the clashes stood at 40, almost all of them rebels, but also including two civilians. The city morgue gave a death toll of 33 militants and two civilians. 43 separatists were also wounded. Separatist leaders Alexander Borodai put the death toll at 34. Ukrainian officials reported no losses. 15 –35 of the rebels were reportedly killed in a single incident when two trucks carrying wounded fighters away from the airport were targeted ether by air strikes or fell into an ambush with at least one of them being hit by an RPG.

During the fighting Druzhba Arena, home of the Kontinental Hockey League team HC Donbass was ransacked by pro-Russian gunmen who looted the arena before destroying surveillance equipment and setting the arena on fire.

Donetsk police said the insurgents had killed two policemen in the nearby town of Horlivka, and it was reported that the men had been executed with sacks over their heads for "breaking their oath to the Donetsk People's Republic".

Lugansk People's Republic militias attacked a Ukrainian National Guard unit in the early morning hours on 28 May. RIA Novosti reported that 80 National Guard members subsequently surrendered to the Lugansk People's Republic forces, while the National Guard issued a statement confirming that "there have been losses both in the ranks of the military unit and the attacking side." At least one separatist and one soldier died in the fighting.

On 28 May, up to 1,000 coal miners marched through Donetsk city in support of the People's Republic, while calling on Ukrainian troops to leave the region.

About half of the separatists killed were identified as Russian citizens, which was confirmed by representatives of the Donetsk People's Republic.

Escalation in May and June
Ukraine's acting defence minister informed that Ukrainian forces had "completely cleared" the southern and western parts of the Donetsk region and the northern part of the Luhansk region of separatists.

On 30 May, six insurgents were killed while they were attempting to retrieve the bodies of their comrades at the site of the airport battle. A spokesperson for the Ukrainian forces said earlier in the day two new attacks on the airport had been repelled with no injuries to their side, Interfax reported. A coup in Donetsk coincided with the repatriation of Russian fighters killed in the airport battle back to Russia.

Luhansk border post siege
On 31 May, two separatists were killed in a firefight with Ukrainian border forces. Also, two days later, five separatists were killed when 500 fighters attacked a border guard base in Luhansk city. 11 border guards and eight separatists were wounded during the fighting, which also killed one civilian. The same day, 7–8 people were killed in an explosion at the occupied regional state administration building. Separatists blamed the incident on a Ukrainian air strike, while Ukrainian officials denied this, with a Ukrainian military spokesman and several Ukrainian media claiming the explosion was caused by a stray surface-to-air missile fired by the insurgents. However, the next day, the OSCE published a report, based on 'limited observation', in which they blamed the explosion on an air-strike. The military admitted conducting over 150 air-strikes during the day in the Luhansk area.

Continued fighting
On 3 June, Ukrainian forces reportedly destroyed the main rebel stronghold in Semenivka and regained control over Krasnyi Lyman. Two soldiers were confirmed killed and 45 wounded. A military spokesman claimed 300 insurgents were killed and 500 wounded in the operation, while the rebels themselves admitted to the loss of 10 –50 fighters, more than 25 of them allegedly being killed while treated in a hospital in Krasnyi Lyman. None of the claims by either side was independently confirmed and both sides denied the other's accounts of the fighting.

On 4 June, rebels captured the besieged border guard base, as well as a National Guard base near Luhansk, after overnight fighting that left six militants dead and three soldiers wounded. Another border guard base was also captured in the town of Sverdlovsk. The National Guard base fell after soldiers there ran out of ammunition, while separatists seized quantities of ammunition and explosives from the Luhansk border guard post.

On 5 June, rebels attacked a border post at the village of Marynivka. The government claimed the fighting left 15–16 rebels dead and five soldiers wounded, while the separatists said they had no information on any losses on their side.

On 7 June, a shootout took place between what witnesses described as rival separatist groups at the Millennium Cafe near the Donetsk administration building. Maxim Petrukhin, vice-chair of the Donetsk People's Republic, was killed in the fight, and chairman Pushilin was also wounded.

Russian tank incursion
On 11 June, Ukrainian officials accused Russia of allowing tanks across the border into Donetsk oblast. "We have observed columns passing with armoured personnel carriers, other armoured vehicles and artillery pieces, and tanks which, according to our information, came across the border and this morning were in Snizhne," Ukrainian Interior Minister Arseny Avakov told reporters in Kiev. He said Ukrainian forces had destroyed part of the column and fighting was still under way. Reuters correspondents confirmed the presence of three tanks in the city, and the US State Department's Bureau of Intelligence and Research confirmed that Russia had indeed sent tanks and other heavy weapons to separatists in Ukraine, including: a column of three T-64 tanks, several BM-21 Grad multiple rocket launchers, and other military vehicles. "Russia will claim these tanks were taken from Ukrainian forces, but no Ukrainian tank units have been operating in that area," the State Department said in a statement. "We are confident that these tanks came from Russia."

President Poroshenko said that it was "unacceptable" for the tanks to be crossing into Ukraine, his press secretary said, while Russia called the confirmed reports "another fake piece of information." The three tanks were then spotted moving through Makiivka and Torez, flying the flag of the Russian Federation. The rebels confirmed they had obtained three tanks, though said they acquired them "from a military warehouse." Pushilin stated that the three tanks would be stationed in Donetsk and that they gave the rebels "at least some hope of defending [Donetsk] because heavy weapons are already being used against us." Konstantin Mashovets, a former Ukrainian Defense Ministry official, said the tanks likely been seized by Russian forces in Crimea before making their way into mainland Ukraine. Anton Heraschenko, an advisor to interior minister Avakov, confirmed at a briefing in Kiev that the tanks were once in the possession of Ukraine’s armed forces in Crimea, and that they had been transferred by sea to Russia before crossing the border into Ukraine.

Late on 12 June, three soldiers were killed when they were ambushed by separatists in the town of Stepanivka.

By the morning of 13 June, fighting resumed as the military continued operations in Mariupol and Ukrainian forces recaptured the city and regained a 75-mile stretch of the border with Russia. Also on 13 June an agreement by Avakov and head of the Donetsk People's Republic Denis Pushilin to create a cease fire and allow for the opening of a humanitarian corridor in Sloviansk failed as both sides blamed the other of continued attacks.

The next morning, a border guard convoy was attacked by guerrillas while passing Mariupol leaving five soldiers dead.

Ilyushin Il-76 shoot-down
On 14 June 2014, an Ilyushin Il-76MD of the Ukrainian Air Force was shot down by forces of the self-proclaimed Lugansk People's Republic during the Ukrainian "anti-terrorist" operation against the Lugansk People's Republic and the Donetsk People's Republic, in its eastern Luhansk and Donetsk oblasts. The aircraft was on approach to land at Luhansk International Airport, and was carrying troops and equipment from an undisclosed location. All 49 people on board died.

On 18 June 2014, it was reported that two T-72 tanks entered Donetsk. At this time, a battle started at a military checkpoint near Luhansk that lasted for two days and left two civilians dead.

Battle of Yampil
Late on 19 June, a battle involving tanks and armored vehicles on both sides erupted at the town of Yampil, near Krasny Lyman. Up to 4,000 separatists were reportedly involved in the fighting which started, according to the rebels, after the military attempted to capture rebel-held Yampil, with the aim of breaking through to the town of Seversk in the Artyomovsk District. According to the military, it started after rebels attempted to break through a cordon of government troops around government-held Krasny Lyman. The battle was described as exceeding "in terms of force and scale anything there has been" in the conflict up-to-date. The military also deployed both air and artillery strikes. The clashes continued into the next day. During the night, 7–12 soldiers were killed and 25–30 were wounded. The military claimed to have killed 300 rebels, but this was not independently confirmed, and although a separatist commander acknowledged heavy losses the separatists confirmed only two deaths on their side and seven wounded. The militants also claimed to had destroyed one tank and several BMDs and shot down a Su-25 bomber.

The Ukrainian military eventually claimed control of this town and Seversk on 20 June, just hours before a unilateral week-long ceasefire. They acknowledged however that there was still heavy fighting going around Yampil and the village of Zakitne. By this point, the number of soldiers killed in the battle had reached 13. During the fighting, militants blew up the bridge over the river in the village of Zakitne.

Donbass People's Militia
Igor Strelkov, commander of the Donbass People's Militia in Sloviansk and alleged Russian Military Intelligence Colonel, has denied Russian involvement in the insurgency. According to him his unit was formed in Crimea, and that 2/3rds of its members are Ukrainian citizens. Strelkov stated that the Sloviansk separatists had agreed to work with the leadership in Donetsk despite conflicts between rebel groups. According to a spokesman for the Donetsk People's Republic, the militants in Sloviansk are "an independent group who are supporting the Donetsk protest," while militants in Sloviansk and Kramatorsk and have identified themselves as members of Pavel Gubarev's Donbass People's Militia.

Militants in Sloviansk appeared to include professional soldiers as well as retired veterans, civilian and volunteers, while those in Donetsk have been confirmed to include former Berkut riot police officers. When asked by The Sunday Telegraph where the weapons had come from, one armed Afghanistan war veteran nodded at the Russian flag flying from the police station and said: "Look at that flag. You know which country that represents." A rebel commander in Donetsk, Pavel Paramonov, has openly told journalists he is from Tula, Russia. In Horlivka, police who defected were commanded by a Lieutenant Colonel of the Russian Army, later to be identified as Igor Bezler. Vyacheslav Ponomarev, the self-declared mayor of Sloviansk and a former military veteran says that he put out an appeal to old military friends to take part in the militia. "When I called on my friends, practically all of whom are ex military, they came to our rescue, not only from Russia but also from Belarus, Kazakhstan and Moldova," he said.

A former separatist militant corroborated the claims in an interview with RFE/RL that fighters have arrived from Russia, including Cossack units, to support the separatists. An interview with an insurgent from St. Petersburg was published in Gazeta who claimed to be fighting voluntarily as part of the "Russian Imperialist Movement."

Army of the South-East
Army of the South-East (Армия Юго-Востока) is the name of a pro-Russian militant group, who have occupied buildings in Luhansk, Ukraine.

According to The Guardian the personnel include former members of the Berkut riot police.

Vostok Battalion
The current Vostok Battalion was formed in early May 2014 and is run by Alexander Khodаkovsky, the head of the Donetsk People's Republic's security service and a militant group called the 'Patriotic Forces of Donbass'. Radio Free Europe has reported that it has members from the original Vostok ("East") Battalion formed in Chechnya by Sulim Yamadayev in 1999, which was used to help pro-Russian separatists from South Ossetia in the Russo-Georgian war. The battalion was incorporated into a Defense Ministry reserve unit based in Chechnya in 2009. Khodakovsky said he had some 1,000 men in his unit now and that some more "volunteers" were coming, with experience of Russian state security structures or the army. However, on the Ukrainian state TV talk show Shuster Live on 13 June 2014, British journalist Mark Franchetti, who had just spent weeks embedded with the Vostok Battalion, described the Vostok Battalion as largely untrained locals from east Ukraine with a smattering of Russian volunteers and stated that the fighters in the Battalion who were now in the Donbass were "mainly normal, ordinary citizens who are absolutely convinced they are defending their homes - as they put it - against fascism". Franchetti stressed that "I can only speak about what I saw with my own eyes".

The original unit which operated in Chechnya, South Ossetia and Georgia was directly controlled by the GRU, Russian military intelligence. The present unit operating in Ukraine, which is partly made of the veterans of the original battalion, was likewise mostly likely re-created by Russian intelligence or with its direct approval. The unit includes both fighters arrived from Russia and Ukrainian-born members.

A number of the Vostok fighters were killed in their first operation in the Donetsk conflict and 30 bodies repatriated back to Russia.

Members of the group are paid salaries of $100 a week.

Cossacks
Insurgents have been found to be members of militant nationalist groups acting as proxies for Russia. On the Russian social network VK, a number of militants involved in the armed seizure of buildings were identified. While some were locals from eastern Ukraine, others were involved in 'self-defense' groups that annexed Crimea. A number were Cossacks from Belorechensk, Krasnodar Krai, Russia, including Registered Cossacks of the Russian Federation. The militants associated with neo-Nazi and ultranationalist groups or imagery.

Don Cossacks volunteers have participated in Ukraine's separatist uprising. The New York Times reported: "It is easy enough to walk across the border, [Ivan P. Doroshev, a commander of a Cossack unit] said. But the Russian government has prohibited Cossack units from crossing en masse. Instead, individual volunteers go to fight."

Several of these Cossacks form a unit called the 'Terek Wolves Sotnia', a reference to a detachment of White emigre Cossacks who fought against Soviet Union during the second world war. Its founder, Andrei Shkuro, is considered Nazi war criminal by the Russian state. Ranking members include Alexander "Boogeyman" Mozhaev (a Russian military veteran from Belorechensk) and Evgeny "Papa" Ponomarev (a Russian Registered Cossack officer), the units Commander. Mozhaev, a fugitive in Russia, states Russian officials have an "an open corridor for the Cossacks" and they are allowed to pass through unchecked and without passports. According to Simon Shuster of TIME, "All of this points to the complicity, if not also the direct orders, of various branches of the Russian government in the Wolves' Hundred campaign – from Russian border guards all the way up to the Kremlin Council for Cossack Affairs."

Following involvement in Crimea, Mozhaev says they "decided to go conquer some more historically Russian lands." The Wolves are part of Cossack militias that have been in the service of Russian President Vladimir Putin, and say they are volunteers driven by the ideals of their Cossack brotherhood, Russian imperialism, and the Russian Orthodox Church. The unit says they will not go home "until they conquer Ukraine or die trying," and claim to have killed numerous Ukrainian servicemen. "We won't just kill them. We will give their bodies back to their mothers in bags," said member Vodolaz, or Diver in a TIME Magazine interview.

On 20 May, Mozhaev issued a video address to Vladimir Putin to open a land corridor to Russia to allow for reinforcements in what he called a "Sacred War." He also explained that his group's goal was to destroy "the Jew-Masons," who are "fomenting disorder all over the world" and "causing us, the common Orthodox Christian folk, to suffer."

On 25 May the SBU arrested 13 Russian Cossacks in Luhansk.

Caucasian armed groups
Ukraine's foreign ministry has said the presence of foreign soldiers amounted to "undisguised aggression" from Russia and "the export of Russian terrorism to our country." "There are grounds to affirm that Russian terrorists funneled on to the territory of Ukraine are being organized and financed through the direct control of the Kremlin and Russian special forces," the ministry said. To dates, reports and interviews have shown the presence of Chechen, Ossetian, Tajik, Afghan, and various Russian paramilitary forces operating in Ukraine.

Chechen paramilitaries
On 4 May 2014 a union of Chechen war veterans announced it would do the same, claiming it had already sent over 1,000 soldiers to Ukraine. On 5 May, it was reported that Chechen rebels were sighted in Sloviansk. According to Sloviansk National Guard commander Stepan Poltorak, the soldiers he witnessed this day were well trained, foreign actors, and "not of Slavic appearance." The next day, the Kyiv Post reported on a YouTube video taken at checkpoint in Sloviansk on 3 May in which the soldiers speak a foreign language, neither Russian or Ukrainian, "fueling suspicions that Chechen soldiers have been sent to eastern Ukraine to cause further unrest." On 7 May Chechen leader Ramzan Kadyrov threatened to send tens of thousands of Chechen "volunteers" to the south of Ukraine if the "junta" in Kiev continued its "punitive operations." It has been reported that Kadyrov has engaged in an aggressive recruitment campaign in Chechnya for this operation, with witnesses claiming of recruitment centres in Grozny, Achkhoy-Martyan, Znamensky, and Gudermes. The Kavkazcenter, the official website of the North Caucasus Islamic insurgency, claimed in mid-March, first, that the Chechen authorities had opened recruiting offices for "volunteers" wishing to fight in Ukraine and then that those offices had been suddenly closed.

The Kavkazcenter posted what it said was a letter it had received from a member of one of the Chechen forces who had been sent to Sloviansk. The man, whom Kavkazcenter identified as "Musa," said morale among his unit was poor because they couldn't understand why they had been sent there and had no grievance against the Ukrainians who, "unlike the Russians, have never done anything bad to us."

On 24 May five trucks ran the Ukraine-Russia border carrying militants aboard, with some reports suggesting among the militants were veteran Chechen soldiers. The following day units of the 'Vostok Battalion' arrived in Donetsk among a group of 8 trucks filled with 20 soldiers each. The soldiers spoke Chechen, and confirmed to the crowd they were from Chechnya. Two told a CNN team they were "volunteers" (and "Kadyrovtsi") from the Chechen capital, Grozny, and one indicated that he was formerly a policemen in Chechnya and in Donetsk to serve the Russian Federation. Russian leader of Chechnya Ramzan Kadyrov denied knowledge of the use of Chechen troops in Ukraine, but separatist commander Sergei "Abwher" Zdrilyuk later confirmed the use of Chechen militants ('and other nationalities') among the ranks of the Donetsk militia, and that many members of the Vostok Battalion were killed in action during a battle with Ukrainian forces at the Donetsk International Airport. Among the dead were confirmed to be members of the 4th-company of the SOBR, a spetsnaz unit of the Russian Interior Ministry (MVD). Donetsk Mayor Oleksandr Lukyanchenko said among wounded militants were Russians from Crimea, Moscow, and the Chechen cities of Grozny and Gudermes.

Chechen militants interviewed by the Financial Times & Vice News confirmed their involvement: “Our president [Chechnya’s Ramzan Kadyrov] gave the order. They called us and we came," one said. They added that their unit was called the "Savage Division," and that they had travelled to Donetsk in a group of 34 soldiers from Grozny via the Russian city of Rostov, and that they were stationed at a Donetsk military base alongside three local pro-Russian paramilitary groups, each of which had its own commander. Asked whether there were Russian fighters on the ground in eastern Ukraine, one replied: “Am I not Russian? [...] The Russians can't openly attack Ukraine...They're not officially here. Everything is underground."

Head of the Chechen Republic Ramzan Kadyrov issued a statement on 1 June, saying that he had not ordered Chechens to take part in the fighting in Ukraine, but in the event he does sent troops, he has "74,000 Chechens who are willing to go to bring order to the territory of Ukraine," and that he would not sent them to Donetsk, but to Kiev.

Ossetians and Abkhaz paramilitaries
On 4 May 2014, the United Ossetia party and the Union of Paratroopers in Georgia's breakaway South Ossetia announced the volunteer recruitment of veterans of the Georgian–Ossetian conflict for "protection of the peaceful population of Ukraine's southeast." Video published by an Osset militant group indicated that they were operating in Donetsk. On 27 May soldiers interviewed admitted that there were 16 fighters from Ossetia operating in Donetsk who had been operating in Donetsk two months prior. Head of the State Border Service of Ukraine Mykola Lytvyn said official records indicate the presence of Abkhaz militants as well.

On 1 June, insurgents from North and South Ossetia were open about their presence to reporters. "In 2008 they were killing us and the Russians saved us. I came here to pay my dues to them," said one named Oleg of the group of 16 within Vostok Battalion.

Russian involvement
A significant number of Russian citizens, many veterans or ultranationalists, are currently involved in the ongoing armed conflict, a fact acknowledged by separatist leaders. Russian specialist for the Security Studies Program at the Massachusetts Institute of Technology Carol Saivets describes the role of Russian soldiers as 'almost certainly' proceeding with the blessing and backing of the Russian state, "even if the Russians are indeed volunteers rather than serving military men."

In an interview with French television station TF1 and radio Europe1 Russian President Vladimir Putin said: "There are no armed forces, no 'Russian instructors' in Ukraine -- and there never were any.".

The well-organized and well-armed pro-Russian militants have been described by Ukrainian media as resembling those which occupied regions of Crimea during the 2014 Russian military intervention in Ukraine. Former Deputy Chief of the General staff of the Ukrainian Armed Forces, Admiral Ihor Kabanenko, claims the militants are Russian military reconnaissance and sabotage units. Interior Minister Avakov stated the militants in Krasnyi Lyman used Russian-made AK-100 series assault rifles fitted with grenade launchers, and that such weapons are only in issue in the Russian Federation. "The Government of Ukraine is considering the facts of today as a manifestation of external aggression by Russia," said Avakov. Militants in Sloviansk arrived in military trucks without license plates.

US State Department spokeswoman Jen Psaki says there is a "broad unity in the international community about the connection between Russia and some of the armed militants in eastern Ukraine". The Ukrainian Government released photos of soldiers in eastern Ukraine, which the US State Department says show that some of the fighters are Russian special forces. US Secretary of State John Kerry said the militants "were equipped with specialized Russian weapons and the same uniforms as those worn by the Russian forces that invaded Crimea." The US ambassador to the United Nations said the attacks in Sloviansk were "professional," "coordinated," and that there was 'nothing grass-roots seeming about it'. UK foreign minister William Hague stated "I don't think denials of Russian involvement have a shred of credibility, [...] The forces involved are well armed, well trained, well equipped, well co-ordinated, behaving in exactly the same way as what turned out to be Russian forces behaved in Crimea." NATO Commander Philip M. Breedlove assessed that soldiers appeared to be highly trained and not a spontaneously formed local militia, and that "what is happening in eastern Ukraine is a military operation that is well planned and organized and we assess that it is being carried out at the direction of Russia."

Russian Opposition MP Ilya Ponomarev said "I am absolutely confident that in the Eastern regions of Ukraine there are Russian troops in very small amounts. And it's not regular soldiers, but likely representatives of special forces and military intelligence."

Klaus Zillikens, head of the OSCE mission in Donetsk, said that the mission has detected signs of "foreign agents" operating in Ukraine, but thus far there is no evidence to confirm that. According to Georgij Alafuzoff, the Director of Intelligence at the European Union Military staff, even if there is presence of the Russian military in Ukraine, it is not as large as it was in Crimea. He suggests the militants are mostly local citizens, disappointed by the situation in the country. Nick Paton Walsh, reporting from Donetsk for CNN, stated that the physical appearance of the militants is different from that of the unidentified troops, spotted throughout Crimea while it was in the process of secession.

David Patrikarakos, a correspondent for the New Statesman said the following: "While at the other protests/occupations there were armed men and lots of ordinary people, here it almost universally armed and masked men in full military dress. Automatic weapons are everywhere. Clearly a professional military is here. There’s the usual smattering of local militia with bats and sticks but also a military presence. Of that there is no doubt."

The New York Times journalists interviewed Sloviansk militants and found no clear link of Russian support: "There was no clear Russian link in the 12th Company’s arsenal, but it was not possible to confirm the rebels’ descriptions of the sources of their money and equipment."

Commenting on the presence of the Vostok Battalion within the rebel ranks, Chairman Denis Pushilin said on 30 May, "It's simply that there were no volunteers [from Russia] before, and now they have begun to arrive – and not only from Russia."

Training facility
In a press briefing by the Ukrainian Secretary of the National Security and Defence Council (NSDC), Andriy Parubiy stated that militants were trained in a military facility in Rostov-on-Don, Russia. "Near Rostov-on-Don, there is a big military base where terrorists are preparing for deployment into the territory of the Ukrainian state. This is confirmed not only by our intelligence, but also Russian prisoners who were detained, and they testify about this base," Parubiy said. He added that more than a thousand militants are trained by Russian instructors, and then they in small armed groups try to break into the territory of Ukraine. On 21 May, a Russian citizen with military experience was detained trying to enter the country, who upon investigation, was found to have recently trained in the Rostov facility.

According to Russian 'volunteer' insurgent organiser Aleksandr Zhuchkovsky, Rostov-on-Don acts as a staging area for the activity where soldiers live in hotels, rented apartments and tent camps.

According to Jen Psaki, the United Stated Department of State is confident that Russia has sent tanks and rocket launchers from a deployment site in southwest Russia into eastern Ukraine, and NATO satellite imagery has shown, as of June 11, 10 main battle tanks stationed across the border at Donetsk in a staging area in Rostov-on-Don.

Pro-government paramilitaries
Several pro-Ukrainian paramilitaries have been formed, and have fought against the Donbass People's Militia and other insurgent groups. These forces include the Donbas Battalion, Azov Battalion, Kharkiv Battalion, and Oleg Lyashko's militia.

Humanitarian concerns
The UN has observed an "alarming deterioration" in human rights in rebel held territory in eastern and southern Ukraine. The UN has detailed growing lawlessness, documenting cases of targeted killings, torture and abduction, primarily carried out by Donetsk People's Republic forces in eastern Ukraine. The UN also reported threats, attacks and abductions of journalists and international observers, as well as the beatings and attacks on supporters of Ukrainian unity.

In a report from the UN Human Rights Monitoring Mission, Ivan Šimonović, UN Assistant Secretary General for Human Rights, reported on illegal detention, abduction and intimidation of election officials and called for urgent action to prevent a Balkans-Style War. He also warned of a humanitarian crisis due to a failure of social services and an exodus of people from the affected region. He said, "Donetsk is on the verge of collapse of social services," due to a shortage of crucial supplies such as medicines including insulin. A medication and insulin shortage was confirmed by Prime Minister Arseniy Yatsenyuk.

In April, the leadership of Donetsk People's Republic requested international assistance and humanitarian aid for its residents.

As of 11 June 225 people were killed in the Donetsk region since the "anti-terrorist operation" began, according to the Ukrainian health ministry. About 15,000 to 20,000 refugees arrived in Svyatogorsk from Slavyansk after the Ukrainian army intensified shelling at the end of May. Most residents of the besieged city are without water, gas, and electricity. Despite that, most residents have remained. Russian officials have claimed that 70,000 refugees had fled across the border into Russia since the fighting began.

Casualties among civilians
2 residents was killed during the attack on the Donetsk airport May 26 .Between 2 and 4 civilians, including women, was killed on May 26 in Slovyansk killed between. According to the Associated Press the fire was from the Ukrainian army June 2nd Ukrainian army committed an airstrike on the center of Lugansk, killing at least seven civilians .On June 8 in Slovyansk few people were killed by artillery shelling, including child. On 14 June two nurses were injured during Ukranian army shelling of Slovyansk, one of them died later. On 15 June three civilians died during shelling Amvrosievka. On 16 June 2 civilians were killed during shelling in Kramatorsk. Four people, including 4-year child died in Slavyansk during 20 June shelling.

Supranational organisations

 * 🇺🇳 UN – A press release issued on behalf of Secretary-General Ban Ki-moon stressed the importance of "constructive and results-oriented dialogue between all concerned", and of adherence to the terms of the Geneva Statement on Ukraine. The statement also made clear that the situation "remains extremely volatile".

States

 * 🇷🇺 Russia – On 7 April Russia's foreign ministry accused Ukrainian authorities of "blaming" the Russian government for all its troubles and stated "Ukrainian people want to get a clear answer from Kiev to all their questions. It's time to listen to these legal claims". It also stated it was "carefully observing" events in the east and south of Ukraine, and again called for "real constitutional reform" that would turn Ukraine into a federation. In an 7 April opinion piece in The Guardian Russian foreign minister Sergei Lavrov wrote that it was the west, and not Russia, that was guilty of destabilising Ukraine and that "Russia is doing all it can to promote early stabilisation in Ukraine". The Russian Foreign Ministry issued a stern condemnation "criminal order" by Kiev for armed aggression against Donetsk, "The Kiev authorities, who self-proclaimed themselves as a result of a coup, have embarked on the violent military suppression of the protests,", demanding that "the Maidan henchmen, who overthrew the legitimate president, to immediately stop the war against their own people, to fulfill all the obligations under the Agreement of 21 February,"
 * Republic of Crimea – Crimean Deputy Prime Minister Rustam Temirgaliyev expressed the hope that the Donetsk Republic (as well as other south-eastern Ukrainian regions) would form a 'Ukrainian Federation' and join the Union State.
 * 🇺🇸 United States – US Secretary of State John Kerry said on 7 April 2014 that the events "did not appear to be spontaneous" and called on Russia to "publicly disavow the activities of separatists, saboteurs and provocateurs" in a phone call to his Russian counterpart Sergei Lavrov. A spokeswoman for the White House National Security Council has noted that the separatists appeared to be supported by Russia. "We saw similar so-called protest activities in Crimea before Russia's purported annexation," she said in a statement, adding: "We call on President (Vladimir) Putin and his government to cease all efforts to destabilize Ukraine, and we caution against further military intervention." US-Ukraine ambassador Geoffrey R. Pyatt characterised the pro-Russian militants as terrorists.