Censor.NET reports citing Al Jazeera.
The report, prepared by a joined committee set up by the UN and the Organization for the Prohibition of Chemical Weapons (OPCW) and seen by Reuters news agency, was presented to the security council on Friday.
The UN experts behind the report said Syrian forces were responsible for a toxic gas attack in the village of Qmenas in Idlib province on March 16, 2015. The committee was unable to determine who was behind two other gas attacks - against Binnish in Idlib province in March 2015 and Kafr Zita in Hama province in April 2014.
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