The alleged attack occurred late on Saturday amid a resumed offensive by Syrian government forces after the collapse of a truce with the Army of Islam rebel group. Douma is the last rebel stronghold in eastern Ghouta, a region that has been subjected to an intensive bombing campaign by Assad’s forces, which are backed by Russia.
The 10-day truce between the two sides collapsed over a disagreement regarding the evacuation of the Army of Islam fighters from the city. Violence resumed days after hundreds of opposition fighters and their relatives left Douma toward rebel-held areas in northern Syria.
The White Helmets, a Syrian civil defense organization, tweeted several photos and videos of alleged victims Saturday night saying “entire families in shelters gassed to death in #Douma #EastGhouta hiding in their cellars, suffocated from the poisonous gas bringing the initial death toll to more than 40.”
The claim has not been verified by NBC News.
Both the Syrian and Russian governments denied any involvement in the alleged chemical attack on Sunday.
The Syrian American Medical Society, which has physicians in the country, said a chlorine bomb hit Douma hospital, killing six people, and a second attack with “mixed agents” including nerve agents had hit a nearby building, Reuters reported.
If confirmed, the use of chemical weapons would be another instance of the banned substances alleged to have been used in Syria’s brutal civil war.
The possible chemical attack comes a year after President Donald Trump launched an attack on a Syrian air base after what U.S. officials said was a chemical attack on the town of Khan Sheikhoun. Trump said at the time that the attack was meant to deter further Syrian use of illegal weapons.
But Nauert said Saturday that Russia, whose involvement in the conflict has helped turn the tide in favor of the Assad regime, “ultimately bears responsibility for these brutal attacks.”
“The United States calls on Russia to end this unmitigated support immediately and work with the international community to prevent further, barbaric chemical weapons attacks,” she said in the statement.
The Syrian government disputed any reports of gas attacks, saying the allegations are an attempt by rebels to stop the army from advancing, according to Syrian state news agency SANA. Russia also denied the reports in a statement from its Defense Ministry on Sunday morning.
“We strongly reject this information and confirm readiness after Douma is liberated from militants to send Russian specialists in radiation, chemical and biological protection to collect data to confirm that these statements are fabricated,” said the statement provided to the TASS news agency. Russia also accused the West of using the allegations to undermine military operations in the area.
After Trump said earlier this week that he wanted to withdraw U.S. troops from Syria, a senior administration official told NBC News that in a meeting with his national security team on Tuesday the president reluctantly agreed to keep forces on the ground for an undetermined period of time to defeat Islamic State.