A chemical weapons watchdog says chlorine was likely used in a suspected gas attack in Syria’s Douma in 2018, stressing that it found no evidence of nerve agent at the site.

The use of chlorine by foreign-backed terrorists is a long-known fact, while nerve agents are usually attributed to the Syrian government which surrendered all its chemical stockpile in 2013.

The new report by the Organization for the Prohibition of Chemical Weapons (OPCW) released on Friday, however, did not assign blame for the incident on a Douma suburb in 2018.

The watchdog said there were “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 Hague-based organization said, noting that it had found no evidence of the use of nerve agents in the Syrian town.

The report was based on a visit by OPCW inspectors to the site of the attack.

The watchdog said it had reached its conclusions based on “witnesses’ testimonies, environmental and biomedical samples analysis results, toxicological and ballistic analyses from experts.”

The Douma attack occurred at a time when the Syrian army was about to win the battle against the foreign-backed militants there. Witnesses said at least 43 people were killed in the incident.

However, Western states were quick to blame the Syrian government for the attack, which Damascus firmly rejected.