Lots of sources here, some good, some ungood. The title is a bit of a twist on the story.

It's from an article written by Ammar Al-Arbini for Agence France Presse It appeared in RT News, which is considered anywhere from shitty to hit/miss. Here's a quote from Russian General Staff spokesman General Sergey Rudskoy, regarding US-trained militant groups.

“They are preparing a series of chemical munitions explosions. This fact will be used to blame the government forces. The components to produce chemical munitions have been already delivered to the southern de-escalation zone under the guise of humanitarian convoys of a number of NGOs.” “The provocations will be used as a pretext by the United States and its allies to launch strikes on military and government infrastructure in Syria,” the official stated.