Although speculation on chemical weaponry has centered around the Syrian government, at least one U.N. investigator is singling out Syrian rebels. Speaking to Swiss-Italian television, Carla Del Ponte, a member of an independent U.N. panel investigating Syria’s civil war, said she has strong suspicions the armed opposition has used sarin nerve gas.

Carla Del Ponte: “We collected some witness testimony that made to appear that some chemical weapons were used, in particular nerving (sic) gas and what appears to our investigation (was) that that was used by the opponents, by the rebels.”