Deir ez-Zor clashes (2011–14)

Protests against the Syrian government and violence has been ongoing in the Syrian city of Deir ez-Zor since March 2011, as part of the wider Syrian civil war, but large-scale clashes started following a military operation in late July 2011 to secure the city of Deir ez-Zor. The rebels took over most of the province by late 2013, leaving only small pockets of government control around the city of Deir ez-Zor. Since late 2014, ISIS became increasingly involved in the rage, but retreated tactically on February. From April 2014, ISIS launched a massive offensive, taking over all rebel areas.

July 2011 – May 2012 clashes
On 31 July 2011, the government sent the Syrian Arab Army into several Syrian cities to control protests on the eve of Ramadan, as part of a nationwide crackdown, nicknamed the "Ramadan Massacre" by opposition activists. One of the cities was Deir ez-Zor.

By 13 August 2011, anti-government activists reported that at least 89 people were killed in the city and its hinterland.

On 17 August, the military ordered a partial retreat of its forces to let a police-guided group of journalist to tour the city. Tanks and armored vehicles moved from the city center to camps on the outskirts.

On 26 November 10 soldiers were killed by defectors in fierce clashes around the city. Several rebel casualties were also reported.

On 4 January 2012, security forces and government loyalists allegedly shot dead at least 22 people, most of them in Deir ez-Zor province, activist groups said. At least 15 civilians died on 10 January.

During UN-brokered cease fire
On 30 April 2012, rebels attacked an army base in the city, killing 12 soldiers. Security forces responded with heavy-machine gun and mortar fire, killing at least one civilian and demolishing a school building.

On 19 May 2012, a car bomb exploded in the town killing nine people. The blast struck a parking lot for a military intelligence complex.

On 22 May, it was reported that two protesters were killed by Syrian police in the presence of U.N observers, who immediately left the area. By this point, it was reported that many towns and villages were under rebel control in Deir ez-Zor province.

June 2012 fighting
On 13 June, hundreds of Syrian Army troops, backed by tanks, stormed Deir ez-Zor in response to attacks by the Free Syrian Army in the past week which managed to destroyed several tanks and APCs and kill dozens of soldiers. Large swaths of the province fell into rebel hands after the alliance between the ruling Alawite elite and Sunni tribes collapsed, leaving government troops with stretched supply lines.

On 20 June, the Syrian army heavily shelled the city of Abu Kamal, held by the Free Syrian Army, on the Iraqi border. Residents of the Iraqi border town of Al-Qaim and activists inside Abu Kamal reported that the shelling of the army had intensified in the past 24 hours, but that the Free Syrian Army still held the city and the important border crossing.

On 23 June, fighting erupted at Deir ez-Zor airport after the FSA made an attempt to capture it. According to the rebels, 40 military officers, including a first-Lieutenant, defected together with their weapons. The result of the fighting remained unclear.

On 24 June, government forces shelled residential areas of the city for the second day, killing at least 20 people, following which, the military withdrew to the outskirts.

On 27 June 10 soldiers were killed while 15 others defected in Deir ez-Zor.

On 28 June, it was reported that the opposition almost entirely controlled the city of Deir ez-Zor, while the military was shelling it, trying to take it back. Human rights activist groups stated that this assault with tanks and artillery had killed over 100 residents. The government also reportedly told doctors not to treat people at local hospitals and targeted hospitals that refused with mortar rounds. Humanitarian aid workers from the Syrian Arab Red Crescent were targeted by the Army, killing one worker.

On 29 June, according to the state news agency SANA, the Army destroyed a rebel pick-up armed with a machine gun, killing all the rebels inside.

On 1 July, five rebels were killed planting an IED near the city.

On 4 July, four soldiers were killed by rebels in Deir ez-Zor. The same day, SANA reported that many rebels had been killed when the Army destroyed six of their cars.

On 7 July, state-controlled news agency SANA reported that army clashed with a rebel group in the al-Sheik Yassin neighborhood, inflicting heavy losses on the rebels. Among the killed were Omar al-To'ma and Qusai Abdul-Majd al-Ani. Four armed pick-up trucks belonging to the rebels were also destroyed during the clash.

July–August 2012 FSA offensive
By 19 July, FSA seized control of all Syrian-Iraqi border crossings. The rebels executed 22 Syrian soldiers under the eyes of Iraqi soldiers and cut the arms and the legs of one colonel, according to the vice minister of Iraq.

Despite previous Iraqi deputy PM statement about FSA taking control of all four border crossing, though it had been confirmed that only 3 of them where still active because the Iraqi government had already closed 1 of them, a Reuters journalist on the Rabia border crossing confirmed that it is still being held by Syrian army, with Iraqi soldiers reporting no activity of Free Syrian Army in the vicinity of the crossing. Three other border crossing with Iraq and Turkey were, however, in rebel hands.

On 21 July, the rebels controlled only the Abu Kamal border crossing with Iraq, adjacent to the city of Abu Kamal, after the arrival of Syrian Army reinforcements to the other two border crossings with the country.

The Guardian made a long report about the fighting in Deir ez-Zor, where 20 rebels groups and the Syrian Army are locked up in a deadly and long stalemate with the rebels claiming to be in control of 90% of the Deiz ez-Zor Governorate.

The al-Nusra Front, the Syrian branch of Al-Qaida, was also increasingly active in fighting the Syrian government in the Deir ez-Zor governorate, at times working directly with the Free Syrian Army, although relations between the groups remain contentious.

On 1 August, the FSA released a video which suggested they had captured the military headquarters in the town of Mayadin. On 3 August, Reuters reported that the FSA had managed to seize a complex for political security and other buildings near Mayadin and also kill 13 security personnel and capture 3 intelligence officers during the battle. A rebel commander in the area also told Reuters that only one army outpost and an artillery position still remained under the control of the Syrian government near Mayadin.

On 7 August, rebels attacked an oil field in the area which resulted in fierce clashes that left four rebels and six to nine soldiers dead. The attack was repelled. On 9 August, the FSA released another video which purportedly showed them seizing a military security complex in Mayadin on 7 August. On 9 August, it was also claimed by British humanitarian Peter Clifford that the Syrian Armed Forces only had three army outposts remaining in the province's countryside and that they were being attacked.

On 13 August, FSA claimed to have shot down a Syrian Air Force MiG-23 over Deir ez-Zor. Shortly afterwards video of its downing was released on YouTube and Syrian opposition and Israel Radio sources the pilot was captured by the rebels. It was the first time government lost a fighter-bomber aircraft. SANA later confirmed the loss of the war-plane, but claimed that plane was not shot down but encountered technical problem which forced it to crash-land and pilot to eject. Later, the rebels published another video showing alleged captured pilot, Colonel Fareer Mohammad Suleiman, in their captivity.

On 14 August, a rebel fighter stationed in the area told PBS Newshour that "all the rural areas are under our control and the cities of Deir ez-Zor, Mayadin and Abu Kamal are a battlefield between us and the Assad army." Later in the day, Reuters reported that the rebels controlled at least 50% of the city of Deir ez-Zour and that the troops remaining in the city were inexperienced and now trapped in security compounds in the city centre and on the northern outskirt.

August 2012 – May 2013 continued fighting
On 22 August, the AFP reported that the FSA seized parts of the city of Abu Kamal, including an intelligence office and military checkpoints. Later that day, Al Jazeera reported from the Iraqi border town of Qaim that Free Syrian Army fighters had launched an attack on the only military base near Al Bukamal still in the hands of the regular army. The army had used this base to shell Al Bukamal. Heavy fighting was ongoing. Also, in the city of Deir ez-Zor, the army only held three bases on the outskirts of the city.

On 1 September, the Guardian reported that the FSA captured an air defense facility in Abu Kamal.

On 4 September, Al Jazeera reported the FSA took control of the head security compound in Deir ez-Zor city, driving loyalist forces out of one of their three remaining bases on the outskirts of the city.

On 5 September, the FSA claimed the Hamdan military airport near Abu Kamal was captured by rebels, after a three day siege and an internal defection. However, rebels later acknowledged that the capture was only temporary, as Syrian troops just outside the base were able to force them to retreat, but also acknowledged that only dozens of Syrian troops in the area were able to survive the onslaught. The Hamdan airport is the last remaining place in the vicinity of Abu Kamal where pro-Assad forces are stationed.

On 28 September, a rebel brigade commander said that the rebels pulled back from al-Qusour and al-Joura neighbourhoods which were than stormed by Syrian army which carried out summary executions. He also said that 80 percent of the city is in hands of FSA with only military airport and part of Mayadin District remaining in government hands. The Syrian Army also launched an operation to recapture the Rashidiya neighbourhood.

On 4 November, rebels captured the Al Ward oil field after three days of heavy fighting.

On 15 November, rebels took control of the military headquarters in Abu Kamal, after fierce clashes with government forces.

On 16 November, rebels seized the military airport of Hamadan, the final place that the government controlled in al-Boukamal. The airport was in fact a base used to transport farm products that was turned into a helicopter base. With fall of Abu Kamal, the main military airport of Deir ez-zor is now the only military airbase in the region, thus creating the largest rebel controlled area in the country.

However, after the fall of Hamada, 12 rebels were killed in the shelling on the outskirts of the city by the army.

By 21 November, rebels controlled two of three major oilfields in the province and were using them to supply themselves with oil. They were preparing for the capture of the remaining one, but needed engineers to operate it. Plans to advance north into Kurdish-dominated Hassakah Province were reportedly also being made. On 30 November, SOHR reported that government troops abandoned the Omar oilfield east of Deir ez-Zor, which was soon occupied by opposition forces. Only five minor fields west of the city still remained under government control.

On 22 November, after 20 days long siege rebels have captured also Mayadin military base from which soldiers evacuated to Deir ez-Zor airbase thus forcing out any government elements from area spanning from Iraqi city to capitol of the province.

On 3 December, fierce combat broke out in the Mouzafin and Joubaila districts of Deir ez-Zor, while rebels reportedly shelled the nearby military airbase.

On 12 December 2012, the French Aid agency, Médecins Sans Frontières called for sick and wounded people to be evacuated from the besieged city.

On 29 January 2013, rebels captured the important Siyasiyeh bridge (and another smaller bridge)on the Euphrates river in Deir Ezzor which connects Deir ez-Zor to Hasakeh, after clashes with the Syrian Army. SOHR director, Rami Abdel Rahman claimed that "Siyasiyeh bridge is the most important in the area as it connects Deir ez-Zor to Hasakeh. Its capture means that army supplies to Hasakeh will be nearly completely severed." and that also "These gains in Deir ez-Zor are very important because this strategic city is the gateway to a region rich in oil and gas resources. If the rebels continue to progress and gain control of what is left of military-held posts, the Pioneers camp and Deir ez-Zor military airport, it will be the first major city to fall into the hands of the rebels." Elsewhere in Deir ez-Zor, activists claimed that rebels had also taken control of a government intelligence complex after five days of heavy fighting, with assistance from Islamist fighters. SOHR claimed that the rebels had taken control of the government complex, including the prison, from which they have freed at least 11 opposition figures. LCC also reported that the rebels captured a tank and three armored personnel carriers.

On 22 February, Free Syrian Army fighters captured a nuclear research facility in Al Kibar from the Syrian Army. The nuclear research facility was the same one which was attacked by an Israeli airstrike back in 2007.

On 6 May, Free Syrian Army shot down a SAA helicopter and killed 8 government soldiers near Deir ez Zor military airport.

June 2013 Hatla massacre
On 10 June, Shia pro-government fighters from the village of Hatla, east of Deir ez-Zor, attacked a nearby rebel position, killing four rebels. The next day, in retaliation for the attack, thousands of rebels attacked and captured the village, killing 60 residents, fighters and civilians, according to SOHR. Rebels also burned civilian houses during the takeover. 10 rebel fighters were killed during the attack. 150 Shia residents fled to the nearby government-held village of Jafra.

On 14 June, the al-Sina'a neighbourhood was bombarded by regular forces at the time when an inhabitants of the neighbourhood were protesting, no reports of human losses. Clashes are taking place between rebel and regular forces in the al-Jbeila and al-Rashdiya neighbourhood after military reinforcements came into al-Jbeila neighbourhood.

On 22 June, violent clashes broke out between rebel and regular forces at the Mashfa al-Qalb (heart hospital) checkpoint of Deir Izzor city. 1 rebel fighter was shot by regular forces at the al-Mawt crossing.

August 2013 rebel offensive
On 11 August, rebels launched fresh offensive to capture the whole city.

On 13 August, clashes took place in Deir Ezzour city in the Rashdin suburb, as regime forces attempt to storm it. Rebels earlier attacked the cardiac hospital in the city, no reports of losses. 4 rebels killed by clashes in al-Jbeila, Hawiqa and Sina'a neighbourhoods.

As of 20 August, the western Hawiqa neighborhood, including the local Baath Party headquarters, had fallen to the rebels. The opposition claimed that 160 government soldiers and dozens of rebels had died in the fight for Hawiqa. Government forces retaliated by bombarding the rebels from their positions in the Joura and Ghazi Ayyash districts. The FSA-affiliated Ahfad al-Rasul Brigade, recently supplied by Qatar with anti-aircraft missiles, played an important role in taking Hawiqa. On the same day, the Army hit rebel forces in Hawiqa district with tanks and multiple rocket launchers, and also battled them in territory separating Hawiqa from the district of Joura, opposition sources in the city said. The government was trying to regain Hawiqa because it could not afford the rebels to be so close to its most important stronghold of Joura and the Army camp there. Air force intelligence and military intelligence, two important security compounds in the city, were also located in the nearby Ghazi Ayyash district, and came within the range of rebel rocket-propelled grenades.

Further rebel progress
On 14 October, SOHR reported that rebels captured the Resefa and Sinaa districts of Deir Ezzor city, as well as Deir Ezzor's military hospital.

On 17 October, well known Syrian Head of Military Intelligence in Deir Ezzor province Major general Jameh Jameh was assassinated by rebels in Deir Ezzor. SOHR reported that he had been shot by a rebel sniper in the Rashdiya district of the city during a battle with rebel brigades.

On 23 November, rebel fighters seized control of Al-Omar oilfield, the largest oilfield in Syria. Its capture meant that the Syrian government had now become almost entirely reliant on imported oil.

On 27 December, rebel fighters seized control over the majority of the town of Al-Jafra, which is adjacent to the Deir Ezzor Military Airbase. However, three days later, Syrian troops, backed by units of the National Defense Force, recaptured Jafra.

On 3 February, the rebels were pushing into the city area, capturing Hamidiyah, Hawiqa, and most of Al-Rashdiya.

On 10 February, the rebels took over all ISIS territory in Deir ez-Zor after all ISIS fighters retreated from the city. The next day, more than 30 FSA battalions and brigades in Deir ez-Zor united under a new coalition called "Mujahidi Deir Al-Zor Assembly".

On 27 March, the rebels blew up a building in the al-Rasafa neighbourhood of Deir Izzor city with confirmed casualties in the ranks of the Syrian Army.

April offensive
On 10 April, ISIS launched a three-pronged assault on rebel positions in and near the border town of Albu Kamal and reportedly took control of parts of the town. This marked the beginning of a two-month offensive that ended when on 14 July, ISIS took control of all rebel-controlled neighborhoods in the provincial capital after expelling Nusra and other rebel groups. One day later ISIS executed the rebel commander of al-Nusra in Deir Ezzor. ISIS also captured all rebel-held towns and villages in the province, leaving them in control of between 95% and 98% of Deir Ez-Zor province.

On 17 August, SOHR said the past two weeks Islamic State (IS) jihadists have killed over 700 tribal members in eastern Syria in oil-rich Deir ez-Zor Governorate which mostly under control  jihadists from Islamic State.

September–November 2014 Army offensive
On 3 September, ISIS launched an attempt to capture the Deir-ez-Zor military airport, but the attempt was repelled and ISIS forces were forced to retreat 3km from the base while the Army launched airstrikes on ISIS positions. According to the Army, ISIS lost at least 47 fighters.

Two days later, General Issam Zahreddine returned to Deir Ezzor with a convoy of 600 Republican Guard soldiers and 90 armed vehicles to reinforce the military airport defense. On 14 September, SAA reportedly destroyed a fortified base belonging to ISIS, killing 14 militants in the process. The next day, Special forces and Syrian Army engineers blew up the Political Bridge, reportedly killing all the militants who were on it. ISIS thus lost the only available land route to move into parts of the city it controls. The offensive intensified on 11 October, when the Army stormed the Al-Ba’ajeen School in the Jubeileh district of the city. The school was used by IS as a headquarter.

On the night of 14 to 15 October, the Republican Guard 104th Brigade reportedly captured the village of Haweeja Saqr near Deir ez-Zor, killing 33 ISIS militants, including four field commanders, and captured another 15. Nine Republican Guard troops, including two officers, died in the fighting. On October 21, ISIS attacked the al-Sina'a industrial quarter of the city. Opposition sources claimed it managed to break through Army defences, but a military source stated that the attack was repulsed and resulted in the death of 23 militants, including Zakaria al-Aboush, a former Free Syrian Army commander of the Ansar al-Islam. Government troops also continuted their offensive against Sakr Island in an attempt to create a buffer zone between ISIS-held areas and the old military airport.

On 24 October, ISIS again failed to storm the al-Sina'a industrial zone, suffering about 50 casualties and dozens of wounded according to the Army. By that point, the 104th was clashing with militants in the north of the island and was controlling most of it according to the Army. The Army claimed that the 104th reached the Al Anafat bridge between Saqr island and the city while remnants of ISIS in the north-eastern part of the island still clashed with government forces on October 26. Two days later, ISIS detonated a car bomb in a residential area on Sakr island, killing 3 civilians and wounding 11 others. The bombing was followed by intense clashes which reportedly left 44 jihadists dead while another 22 were captured. An ISIS drone was downed over the cemetery on the next day. According to the Army, government troops killed another 120 insurgents from 29 to 31 October, and managed to assert control over 90% of Sakr Island.

On 12 November, government troops reportedly captured the western bank fisheries on Sakr Island, which were used by ISIS to travel back and forth from the island to the mainland. A small network of tunnels was also discovered. ISIS suffered more casualties on 20 November after the 104th Brigade attacked their supply bases, sniper hideouts and repelled infiltration attempts. At least 33 militants were killed and 15 captured. ISIS positions in the Central Park on Sakr Island were further weakened.

On 28 November, according to the Army, its units carried out raids against ISIS positions in the Central Park on Sakr Island. It claimed that at least 17 ISIS fighters were killed and 24 were arrested throughout the city.

December 2014 ISIS Offensive
On 3 December, ISIS launched an offensive in the direction of the Deir Ezzor military airbase. They reportedly managed to capture the al-Masemekeh Building after a suicide bomber detonated a car near it. The next day, ISIS reportedly advanced further and captured Al Mari'iyah village and also captured parts of the al-Jafra village, On 5 December, ISIS captured the al-Jafra village.

On 5 December, the Army launched a counter-attack and recaptured parts of Al Mari'iyah village and regained control of perimeter the Deir-ez Zour airbase from ISIS. The Army claimed that it had killed over 100 ISIS militants since the start of the ISIS offensive. According to the SOHR, ISIS managed to capture some positions and military equipment on the mountain overlooking the city.

During the night of 6 November, ISIS took control over the missiles battalion to the northeast of the Airport and tried to storm the air base, but failed. ISIS also pulled back from the mount overlooking Deir ez Zor after it was exposed by heavy aerial bombardment, which reportedly used chlorine. Since the start of the offensive, 51 soldiers and 68 ISIS militants were killed.