A senior U.S. military officer says preliminary tests show traces of the chemical agent sulfur mustard on mortars that Islamic State militants used to attack Kurdish forces in Iraq.
U.S. Brigadier General Kevin Killea said the field test was not conclusive proof of chemical weapons use and that the fragments are undergoing more definitive testing to confirm the finding.
U.S. officials have been looking into reports that Islamic State militants used the chemical weapon mustard gas in the August 11 attack in Makhmour.
Speaking to reporters in Washington on August 21, Killea said fragments of the shells were collected by the Kurdish fighters and handed over to U.S. forces in the region.
"We were able to take the fragments from some of those mortar rounds and do a field test...on those fragments, and they showed the presence of HD, or what is known as sulfur mustard," Killea said.