Use of chemical weapons in the Syrian civil war

Use of chemical weapons in the Syrian Civil War has been confirmed by the United Nations. The deadliest attacks were the Ghouta attack in the suburbs of Damascus in August 2013 and the Khan al-Asal attack in the suburbs of Aleppo in March 2013. Several other attacks have been alleged, reported and investigated.

A U.N. fact-finding mission and a UNHRC Commission of Inquiry have simultaneously investigated the attacks. The U.N. mission found likely use of the nerve agent Sarin in the case of Khan Al-Asal (19 March 2013), Saraqib (29 April 2013), Ghouta (21 August 2013), Jobar (24 August 2013) and Ashrafiyat Sahnaya (25 August 2013). The UNHRC commission later confirmed the use of Sarin in the Khan al-Asal, Saraqib and Ghouta attacks, but did not mention the Jobar and the Ashrafiyat Sahnaya attacks.That Sarin was used in Khan al-Asal was also the conclusion of the Russian investigation of the attack.

The UNHRC commission also found that the Sarin used in the Khan al-Asal attack bore "the same unique hallmarks" as the Sarin used in the Ghouta attack and indicated that the perpetrators likely had access to chemicals from the Syrian Army's stockpile.

Background
The use of chemical weapons must be seen in the context of the Syrian Civil War. On 20 August 2012, President Barack Obama used the phrase "red line" in reference to the use of chemical weapons. On 6 September 2013 a bill was filed to authorize the use of military force against the Syrian military, mainly in response to the use of sarin in the Ghouta attack on 21 August 2013. On 9 September 2013, the U.S. Secretary of State John Kerry stated that the air strikes could be averted if Syria turned over "every single bit" of its chemical weapons stockpiles. Hours after Kerry's statement, the Russian foreign minister Sergey Lavrov announced that Russia had suggested to Syria that it relinquish its chemical weapons. The Syrian foreign minister Walid al-Moallem immediately welcomed the proposal.

Prior to September 2013 the Syrian government had not publicly admitted to possess chemical weapons, although Western intelligence services believed it to hold one of the world's largest stockpiles.

Incidents
The map marks the position of reported chemical weapons attacks in the Syrian Civil War.

The table below list the reported attacks and the main points. See the main articles for details.

Other related incidents
In December 2012, the chemical plant SYSACCO 29 km east of Aleppo was taken by rebel fighters from the Al-Nusra Front. The factory produces chlorine among other chemicals. On 5 November 2014, the Syrain UN-ambassador Bashar al-Jaafari, said "terrorist organizations stole about 200 tons of [chlorine gas] from" the factory.

On 30 May 2013, Turkish newspapers reported that Turkish security forces had arrested Al-Nusra Front fighters in the southern provinces of Mersin and Adana near the Syrian border and confiscated 2 kg of sarin gas. The Turkish Ambassador to Moscow later said that tests showed the chemical seized was not sarin, but anti-freeze (anti-freeze is either Methanol or Isopropyl alcohol). In September six of those arrested in May were charged with attempting to acquire chemicals which could be used to produce sarin; the indictment said that it was "possible to produce sarin gas by combining the materials in proper conditions."

According to Syria, on 1 June 2013, the Syrian Army seized two cylinders holding the nerve agent sarin from Syrian opposition fighters in Hama. A Syrian military source told SANA, the official news agency in Syria, that the Syrian Army seized two containers with sarin together with automatic rifles, pistols and homemade bombs (IEDs) in a rebel hideout in the al-Faraieh neighborhood (also spelled Al-Faraya) of the city of Hama,  which has been the scene of fighting between government troops and armed opposition groups. The Syrian government declared the two cylinders "as abandoned chemical weapons" and told the OPCW that "the items did not belong to" them. On 14 June 2014, the Joint OPCW-UN Mission confirmed that the cylinders contained sarin. On 7 July 2014, the U.N. Secretary-General Ban Ki-Moon informed the U.N. Security Council about the findings.

The UN mission to investigate alleged use of chemical weapons
The United Nations Mission to Investigate Allegations of the Use of Chemical Weapons in the Syrian Arab Republic was a fact-finding mission to investigate possible use of chemical weapons in Syria. On 16 September 2013 the mission published a report with focus on the Ghouta attacks. On 12 December 2013, the UN mission delivered its final report.

The UNHRC commission of inquiry
The Independent International Commission of Inquiry on the Syrian Arab Republic was set up by the United Nations Human Rights Council (UNHRC) on 22 March 2011 to investigate human rights violations during the Syrian civil war. In its report dated 12 February 2014 they confirmed the use of Sarin in the case of Khan Al-Assal (19 March 2013), Saraqib (29 April 2013) and Al-Ghouta (21 August 2013). The UNHRC commission also found that the Sarin used in the Khan al-Asal attack bore "the same unique hallmarks" as the Sarin used in the Ghouta attack and indicated that the perpetrators likely had access to chemicals from the Syrian Armys stockpile.

In its report dated 13 August 2014 they accused Government forces of using chlorine gas in 8 incidents in Idlib and Hama governorates in April 2014.

The Russian Khan al-Asal investigation
A Russian team investigated the Khan al-Asal incident on 19 March 2013. The Russian UN ambassador Vitaly Churkin delivered a report with analysis of the samples taken at the site to the UN Secretary General Ban Ki-moon on 9 July 2013. They declared that the sarin had been produced in "cottage industry" conditions without the use of chemical stabilisers and that the Sarin contained diisopropyl fluorophosphate.

Though the Russian report was not published certain Russian findings were restated by Vitaly Churkin. The rebels, the Russians maintained, launched an unguided "Basha'ir-3" projectile towards Khan al-Assal. The results of the analysis clearly indicated, according to the Russians, that the ordnance used in Khan al-Assal was not industrially manufactured and that the sarin was not industrially manufactured either. According to the Russians the production of "Basha'ir-3" unguided projectiles was started in February 2013 by the Basha'ir al-Nasr Brigade affiliated with the Free Syrian Army. In the final United Nations report the picture was one of contradicting information. The United Nations Mission was not able to collect any “untouched” artifacts relevant to the incident and necessary for an independent verification of the information gathered. No biomedical samples were handed over to the United Nations Mission by the Syrian Government. The UN report did not concur with the Russian results. In 2014 the U.N. concluded that the 8/21 Sarin bore the ‘same unique hallmarks’ as the Sarin used in the 3/19 Khan al-Assal attack. Describing the attack on the Ghouta district near Damascus, the report said: "The perpetrators likely had access to the chemical weapons stockpile of the Syrian military, as well as the expertise and equipment necessary to manipulate safely large amount of chemical agents."

The OPCW Fact-Finding Mission in Syria
On 29 April 2014, the Director General Ahmet Üzümcü of the Organisation for the Prohibition of Chemical Weapons (OPCW) announced the creation of an OPCW mission to establish the facts surrounding allegations of the use of chlorine gas for hostile purposes in Syria. The Syrian Government has agreed to the mission.

On 27 May 2014, members of the mission were ambushed and briefly held by gunmen in rebel-held territory as it headed toward Kafr Zita to investigate the alleged chlorine gas attacks. The opposition Hama Media Centre said the attack on the convoy was carried out by Assad's forces.

Other allegations
In February 2012, a defected lieutenant who worked in the chemical weapons department claimed that "BZ-CS, Chlorine Benzilate, which damages people’s nerves and makes them fade away, is being used in Bab Amr." He said that some Syrian soldiers had been supplied with gas masks for protection.