OPCW: In 2018, "at least one helicopter of the Syrian 'Tiger Forces' Elite Unit dropped two yellow cylinders containing toxic chlorine gas on two apartment buildings in a civilian-inhabited area in Douma, killing 43 named individuals and affecting dozens more." https://www.opcw.org/media-centre/news/2023/01/opcw-releases-third-report-investigation-and-identification-team #news #syria
The report addresses the theory, promoted by Russia, Syria and their useful idiots, that the attack was a "false flag" by rebels (p. 38). OPCW investigators even visited the supposed chemical weapons factory ID'd by the Assad regime -- and found nothing to support the conspiracy narrative.
https://www.opcw.org/sites/default/files/documents/2023/01/s-2125-2023%28e%29.pdf