The suspicions have the Obama administration calling for an immediate U.N. investigation into the "abhorrent acts" -- though it remains unclear what, if any, punishment Bashar Assad might face if formally blamed for the string of alleged chlorine gas attacks.
One western U.N. diplomat told Fox News the situation has become "unacceptable" in Syria.
"There is mounting evidence of repeated chlorine attacks," the diplomat said. » | FoxNews.com | Thursday, May 07, 2015