A mass grave in a town outside Damascus contains the bodies of at least 100,000 people, the head of a US-based Syrian advocacy organisation has claimed.

The people are said to have been killed by the former government of Bashar al-Assad, which suppressed any sign of dissent.

Mouaz Moustafa, speaking to Reuters from Damascus, said the site at al-Qutayfah, 25 miles north of the Syrian capital, was one of five mass graves that he had identified.

“One hundred thousand is the most conservative estimate” of the number of bodies buried at the site, said Mr Moustafa, head of the Syrian Emergency Task Force. “It’s a very, very extremely, almost unfairly conservative estimate.”