commission accused the Syrian government and armed opposition groups of committing war crimes and inflicting "immeasurable suffering" on civilians, in a scathing report released Wednesday that left no side without blame.
The report, the eighth prepared by a commission investigating possible war crimes in Syria, was based on 480 interviews and evidence collected between Jan. 20 and July 15.
According to the report, witnesses saw helicopters drop barrel bombs and smelled a scent similar to domestic chlorine.
Medical personnel administering to the victims provided "descriptions of symptoms compatible with exposure to chemical agents, namely vomiting, eye and skin irritation, choking and other respiratory problems," the report said. "There are also reasonable grounds to believe that those agents were dropped in barrel bombs from government helicopters flying overhead."
Government forces also continue to perpetrate massacres and conduct systematic torture, rape and enforced disappearances against civilians, the report said.
"Public squares have become the scene of amputations, lashings and mock crucifixion," the report said. Public executions are a "common spectacle" on Fridays, with the Islamic State encouraging residents to attend.