The Russian military has charged that Syrian militants used a toxic agent against civilians in Aleppo, killing seven and sickening another 23 people.
The head of Russian military's Reconciliation Center at the Hemeimeem air base in Syria, Lieutenant General Sergei Chvarkov, said on August 3 that the rebels struck a residential area in eastern Aleppo with a toxic agent.
Chvarkov didn't identify the substance used in the attack, which he said occurred on August 2, but he said the victims suffocated or suffered lung burns.
Chvarkov said the attack was launched by Nour el-Deine Zengi, a militant group he said had been considered by the United States as part of the moderate opposition.
He said the Russian military had informed the United States about the incident.
Nour el-Deine Zengi didn't immediately issue a response to the allegations.
The Russian claim came a day after the Syrian Observatory for Human Rights reported 24 people suffered breathing difficulties in rebel-held Saraqeb, a town south of Aleppo, after a barrel-bomb attack.
Residents said chlorine gas had been used in the attack.
