Damascus dead have mouths full of foam
Activists cry 'genocide' and nurse describes classic symptoms of nerve gas poisoning
They are among the most horrific images of the two-year Syrian civil war - many too shocking to show.
Rows of pale lifeless bodies of children lined up on floors of makeshift hospitals and others with oxygen masks on their faces as paramedics attended to them.
The dead, many of them women, arrived with their pupils constricted, cold limbs and foam in their mouths.
Extensive amateur video and photographs posted by activists on the internet yesterday showed countless bodies with no sign of outward injury. Other videos showed children seeming to twitch uncontrollably.
"The doctors say these are typical symptoms of nerve gas victims," said one nurse at Douma emergency collection facility.
"Genocide! Genocide in the town of Moadamiyet al-Sham [southwest of Damascus] using chemical weapons," cried one man behind a camera.
His voice trembling with fear, he adds: "Where are my parents? Where is my father? My mother?"
These were the apparent victims of a Syrian government toxic gas attack the main opposition group branded a "massacre" in the eastern suburbs of Damascus.
The death toll could not be verified, but figures given by the opposition and medical workers said hundreds had died, possibly as many as 1,300.
The toll, if proven, would make it the deadliest single day since the revolt against President Bashar al-Assad's regime began in mid-March 2011.
In a statement read by a uniformed officer on Syrian state television, the army said the reports were part of a "media war" designed to prevent Syria from fighting terrorists. The Syrian government regularly refers to the opposition as terrorists.
Chemical weapons experts said the symptoms depicted in the videos were inconsistent with the use of a conventional chemical weapon, like sarin or mustard gas.
Gwyn Winfield, editor of CBRNe World, a professional journal that covers nonconventional weapons, said the images suggested the possible use of a large amount of a crowd control agent like tear gas in a confined space or a weakened form of a more powerful chemical agent.
An activist reached via Skype in Erbeen said the attack began at 2am, when rockets struck surrounding areas.
"I saw many children lying on beds as if they were sleeping, but unfortunately they were dead," said the activist, who gave his name as Abu Yassin. He added that he believed the number of dead was in the hundreds.
"We thought this regime would not use chemical weapons, at least these days with the presence of the UN inspectors," he said. "It is reckless. The regime is saying, 'I don't care.'"
Another activist, who gave only his first name, Mohammed, said he was in Zamalka when the rockets landed. He was helping to evacuate the wounded when his eyes started burning, his vision went blurry and he felt dizzy.
Many opposition leaders noted that the attack came nearly one year after President Barack Obama declared the use of chemical weapons a "red line" that could lead to a stronger American response. US officials in June said they believed that Assad's forces had used chemical weapons "on a small scale" several times in the last year, but that did not lead to a substantive change to US involvement in the conflict.
The New York Times, Reuters, Agence France-Presse