The global chemical weapons watchdog has concluded that chlorine was likely used in an attack on the Syrian town of Douma last April.
Inspectors at the Organisation for the Prohibition of Chemical Weapons (OPCW) said on Friday that a “toxic chemical” containing chlorine was used in the attack on the town, at the time held by rebels but besieged by pro-government forces.
Washington blamed the Syrian government and said it had used chemical weapons. Damascus denies having ever used chemical weapons.
During an investigation in mid-April, inspectors from the OPCW visited two sites in Douma to interview witnesses and take samples, which have been analysed in OPCW-affiliated national laboratories.
The investigation did not assign blame, but the information gathered provided “reasonable grounds that the use of a toxic chemical as a weapon has taken place on 7 April 2018”.
“This toxic chemical contained reactive chlorine. The toxic chemical was likely molecular chlorine,” the OPCW said in a statement.
Weaponising chlorine is prohibited under the Chemical Weapons Convention, ratified by Syria in 2013, and is prohibited under customary international humanitarian law.
The OPCW has documented systematic use of the banned nerve agent sarin and chlorine in Syria’s civil war, now nearing its eighth year.
From 2015 to 2017 a joint UN-OPCW team had been appointed to assign blame for chemical attacks in Syria. It found that Syrian government troops had used the nerve agent sarin and chlorine barrel bombs on several occasions, while the Islamic State of Iraq and the Levant (ISIL or ISIS) fighters were found to have used sulphur mustard.
In June, the OPCW’s member states granted the organisation new powers to assign blame for chemical weapons attacks, but that was not the mandate of the team that carried out the Douma inquiry.
The latest OPCW report “adds one more case to the scores of illegal chemical weapons attacks confirmed since 2013”, said Lou Charbonneau of the New York-based Human Rights Watch.
“It’s clear that the organisation’s new unit for attributing blame for chemical weapons attacks in Syria has its work cut out. Those responsible for the use of these banned weapons should be unmasked and held to account.”
The OPCW is also looking into an alleged gas attack last November in Aleppo that reportedly made up to 100 people ill. The Syrian government and its ally Russia blamed that attack on rebels.