The Organization for the Prohibition of Chemical Weapons (OPCW) on Friday accused Syria of carrying out a chlorine attack that killed 43 people in 2018. The incident sparked tensions between Damascus, the Syrian capital and the West .
According to a highly anticipated report by OPCW investigators, "there are reasonable grounds to believe" that at least one Syrian Air Force helicopter dropped two barrels of poison gas on the town of Douma, near of Damascus during the civil war.
Damascus and its ally Moscow (Russia) claimed the attack was staged by relief workers at the request of the United States, which launched airstrikes on Syria a few days later along with the United Kingdom and the France.
The case had also sparked controversy after reports leaked that two former employees of the OPCW, based in The Hague (Netherlands), had questioned the findings of an earlier investigation.
But the OPCW said its investigators had "considered a series of possible scenarios" and concluded that "the Syrian Arab Air Force is the perpetrator of this attack".
Two yellow cylinders
"The use of chemical weapons in Douma and elsewhere is unacceptable and a violation of international law," said OPCW Director General Fernando Arias.
“The world now knows the facts.
It is up to the international community to act, at the OPCW and beyond,” he added.
"At least one Syrian Arab Air Force Mi-8/17 helicopter, departing from Dumayr Airbase and operating under the control of the Tiger Forces, dropped two yellow cylinders, which hit two buildings residential in a central area of the city,” the report reads.
A cylinder hit a roof, 'ruptured and rapidly released toxic gas, chlorine, in very high concentrations, which rapidly dispersed throughout the building, killing 43 identified people and affecting dozens more “, says the report.
The second cylinder slammed into an apartment, partially split open and "started to slowly release chlorine, slightly affecting those who arrived on the scene first", he added.
Investigators analyzed samples taken from the scene, interviewed survivors and witnesses, and conducted ballistics tests, including "cylinder drop tests."
They also examined video and photographic evidence, satellite images, computer diagrams and solicited experts.
The Syrian regime denies access to the site
Douma was controlled by rebels at the time of the incident, which occurred during a major offensive by Syrian government forces to retake the city.
Rescuers said at the time they treated people with breathing problems, foaming at the mouth and other symptoms.
Damascus and Moscow have accused rebels and rescuers of staging the attack and bringing dead bodies to the scene.
They also claimed that an Islamist chemical weapons factory had been hit.
But OPCW investigators said there was no evidence to support the claims.
The team "meticulously reviewed the investigative leads and scenarios suggested by the Syrian authorities and other state parties, but was unable to obtain concrete supporting information", the body said.
The OPCW also says it "regrets" that Syria refused to allow it access to the site to investigate, despite various requests and Damascus' obligations under the Chemical Weapons Convention.
The report also rejects claims by former investigators that the OPCW changed the initial findings of a 2018 investigation, in an effort to make evidence of a chemical attack more conclusive.
Syria denies the use of chemical weapons and claims to have handed over its stockpiles as part of a 2013 deal sparked by an alleged sarin gas attack that killed 1,400 people in the Damascus suburb of Ghouta.