U.N. inspectors said in a report Monday there is "clear and convincing evidence" that chemical weapons were used on a relatively large scale in an attack last month in Syria that killed hundreds of people.
The findings represent the first official confirmation by scientific experts that chemical weapons were used in the Syrian conflict, but the first page of the report, seen by The Associated Press, left the key question of who launched the attack unanswered.
The report came as the chairman of a U.N. war crimes panel said it is investigating 14 suspected chemical attacks in Syria, dramatically escalating the stakes after diplomatic breakthroughs that saw the Syrian government agree to dismantle its chemical weapons program.
Secretary-General Ban Ki-moon was scheduled to present the U.N. inspectors' report to the U.N. Security Council later Monday morning.
The inspectors said "the environmental, chemical and medical samples we have collected provide clear and convincing evidence that surface-to-surface rockets containing the nerve agent sarin were used ... in the Ghouta area of Damascus" on Aug. 21.
"The conclusion is that chemical weapons have been used in the ongoing conflict between the parties in the Syrian Arab Republic, also against civilians, including children, on a relatively large scale," the inspectors said in their report to Ban.
"This result leaves us with the deepest concern," the inspectors said.