Report suggest Rebels gassed Damascus civilians by accident.
Came across this a short time ago in the http://www.mintpressnews.com/. So far I've only found one report suggesting that it was rebels who caused the chemical release accidentally.
EXCLUSIVE: Syrians In Ghouta Claim Saudi-Supplied Rebels Behind Chemical Attack
Rebels and local residents in Ghouta accuse Saudi Prince Bandar bin Sultan of providing chemical weapons to an al-Qaida linked rebel group.
Clarification: Dale Gavlak assisted in the research and writing process of this article, but was not on the ground in Syria. Reporter Yahya Ababneh, with whom the report was written in collaboration, was the correspondent on the ground in Ghouta who spoke directly with the rebels, their family members, victims of the chemical weapons attacks and local residents.
"....from numerous interviews with doctors, Ghouta residents, rebel fighters and their families, a different picture emerges. Many believe that certain rebels received chemical weapons via the Saudi intelligence chief, Prince Bandar bin Sultan, and were responsible for carrying out the dealing gas attack."
“My son came to me two weeks ago asking what I thought the weapons were that he had been asked to carry,” said Abu Abdel-Moneim, the father of a rebel fighting to unseat Assad, who lives in Ghouta.
Abdel-Moneim said his son and 12 other rebels were killed inside of a tunnel used to store weapons provided by a Saudi militant, known as Abu Ayesha, who was leading a fighting battalion. The father described the weapons as having a “tube-like structure” while others were like a “huge gas bottle.”
Ghouta townspeople said the rebels were using mosques and private houses to sleep while storing their weapons in tunnels.