Bassem Mirhaj al-Hassan, a senior Assad regime official and former head of the Presidential Security and Military Office, was one of the central architects of Syria’s chemical weapons campaign. As Assad’s key security adviser and overseer of chemical weapons logistics, Bassem directed and facilitated more than 200 chemical attacks between 2012 and 2018, resulting in the deaths of over 1,500 civilians and injuring thousands more. He also played a central role in organizing militias, assassinations, and systemic war crimes across Syria, including cross-border operations in Lebanon. View the full dossier on Bassem and other war criminals at setf.ngo/cards