Alleged Syrian gas attack kills hundreds around Damascus

Syria's opposition accused government forces of gassing at least 1,300 people on Wednesday by firing rockets that released deadly fumes over rebel-held Damascus suburbs, killing men, women and children as they slept in the wee hours of the morning.

Images, including some by freelance photographers supplied to Reuters, showed scores of bodies - some of them small children - laid on the floor of a clinic with no visible signs of injury. Some showed people with foam around their mouths.

Shells and rockets fell at around 3 am local time on Wednesday.

One man told Reuters he had helped retrieve victims in the suburb of Erbin. "We would go into a house and everything was in its place. Every person was in their place. They were lying where they had been. They looked like they were asleep."

Doctors interviewed described symptoms point to sarin gas, one of the agents Western powers accuse Damascus of having in an undeclared chemical weapons stockpile.

Syrian information minister Omran Zoabi said the allegations were "illogical and fabricated". Assad's officials have said they would never use poison gas against Syrians.

The United States and its European allies believe Assad's forces have used small amounts of sarin before; which is mainly why an emergency UN meeting was held late on Wednesday in New York.

An opposition monitoring group, citing figures compiled from clinics in the Damascus suburbs, put the death toll at 494 - 90 per cent killed by gas, the rest by bombs and conventional arms. The rebel Syrian National Coalition said 650 people died.

Activists said rockets with chemical agents hit the Damascus suburbs of Ain Tarma, Zamalka and Jobar during a fierce pre-dawn bombardment by government forces. The Damascus Media Office said 150 bodies were counted in Hammouriya, 100 in Kfar Batna, 67 in Saqba, 61 in Douma, 76 in Mouadamiya and 40 in Erbin.

A nurse at Douma Emergency Collection facility, Bayan Baker, said: "Many of the casualties are women and children. They arrived with their pupils constricted, cold limbs and foam in their mouths. The doctors say these are typical symptoms of nerve gas victims."

Extensive amateur video and photographs appeared on the internet showing victims choking, some foaming at the mouth.

A video purportedly shot in the Kafr Batna neighbourhood showed a room filled with more than 90 bodies, many of them children and a few women and elderly men. Most of the bodies appeared ashen or pale but with no visible injuries.

Other footage showed doctors treating people in makeshift clinics. One video showed the bodies of a dozen people lying on the floor of a clinic. A voiceover said they were members of a single family. In a corridor outside lay another five bodies.