Beirut: The opposition Free Syrian Army is creating a unit of men trained to secure Syria’s chemical weapons sites, said a former general in the country’s chemical and biological weapons administration.

“We have a group just to deal with chemical weapons. They are already trained to secure sites,” said General Adnan Silou, the most senior member of Bashar Al Assad’s regime to join the FSA. Until 2008 Gen Silou was responsible for drafting emergency response plans should any of Syria’s weapons fall out of the government’s control.

He trained troops in how to secure what analysts believe are the largest chemical weapons stores in the world, consisting principally of sarin, mustard gas and cyanide. “We trained them in securing stores, in reconnaissance of possible threats, in how to purge supplies and in treatment should Syria come under a chemical or biological attack,” said General Silou.

“There were two main stores — warehouse 417 in east Damascus and number 419 in the Homs area. We had 1,500 soldiers and two or three generals stationed at each base.”

As the Syrian regime’s rule begins to unravel, the question of how to maintain the security of these sites has become a concern. Gen Silou fears that the Assad regime could yet deploy some of the stores in a desperate attempt to retain control.

“I know Bashar Al Assad’s character. It is very possible that he will use the chemical weapons against his own people,” he said. “They can deploy them from tanks, from rockets, and from helicopters”.

Gen Silou came out of retirement and joined the FSA leadership in Turkey following the attack on Homs in February. He is convinced that the regime sprayed pesticides from planes on populated areas in Rastan, a hub for the Free Syrian Army close to Homs.

The claims cannot be independently confirmed, but doctors in Lebanon treating Syrian patients who had fled from Rastan and Homs in the spring reported seeing unusual symptoms. “We are now scanning all Syrian military defectors for people with training on chemical weapons,” said Louay Al Mokdad, an opposition activist. “We are putting them in one unit that can work to secure the sites.”