Investigators also detail August chlorine attack allegations . The U.S. military has said it is investigating the allegations, but no evidence of chemical weapons use was found in any of those attacks. Asked about the revelation of additional Syrian chemical weapons facilities , State Department spokeswoman Jen Psaki pointed to a recent statement from Secretary of State John Kerry , which said the United States was `` gravely concerned '' about the recent reports of chlorine attacks in Syria . ` A U.N. special envoy briefs the Security Council on lingering chemical weapons . Syria has four chemical weapons facilities it did n't previously disclose .
Investigators also detail August chlorine attack allegations . The U.S. military has said it is investigating the allegations, but no evidence of chemical weapons use was found in any of those attacks. A U.N. special envoy briefs the Security Council on lingering chemical weapons . Syria has four chemical weapons facilities it did n't previously disclose .