AMMAN, Jordan — A leading Syrian opposition figure said on Wednesday 1,300 people had been killed in attacks by President Bashar al-Assad's forces around Damascus in which he said chemical weapons had been used.

"Today's crimes are...not the first time the regime has used chemical weapons," George Sabra told a news conference in Istanbul. "But they constitute a significant turning point in the regime's operations...This time it was for annihilation rather than terror."

Syria denied activist reports on Wednesday that the army had used chemical weapons, describing the assertions as completely untrue. Video footage from districts east of the capital showed people choking, some of them foaming at the mouth, and many bodies with no signs of injuries.

The United States and European countries say they believe Assad's government has used poison gas including the nerve agent Sarin in the past, which Washington called a "red line" that justified international military aid to the rebels.

Khaled Omar of the opposition local council in Ain Tarma said he saw at least 80 bodies at the Hajjah Hospital in Ain Tarma and at a makeshift clinic at Tatbiqiya School in the nearby district of Saqba.

"The attack took place at around 3:00 AM (0000 GMT). Most of those killed were in their homes," Omar said.