FILE – This file image made from video broadcast on Syrian State Television on Tuesday, Oct. 8, 2013, purports to show a chemical weapons expert taking samples at a chemical weapons plant at an unknown location in Syria. The Islamic State group is aggressively pursuing development of chemical weapons, setting up a branch dedicated to research and experiments with the help of scientists from Iraq, Syria and elsewhere in the region, according to Iraqi and U.S. intelligence officials. (Syrian State Television via AP video, File)