The sources accused Syrian regime forces, who have now taken full control of the town, of carrying out the attack in order to delay the worldwide investigation into the suspected use of chemical weapons by the Russian-backed Syrian regime which killed at least 49 civilians last week.
On Tuesday, Syrian state media said air defence had shot down missiles over the central province of Homs, with the strikes reportedly targeting regime air bases.
The Pentagon denied any American military activity in the area.
Journalists were allowed access to Douma on Monday.
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Ms Andrea Constand said she had called him as she drove to his home in January 2004 when she claimed he sexually assaulted her. Cosby's first trial ended in June when a different jury deadlocked on all charges after more than 50 hours of deliberations.
The team's entry into Douma came 10 days after the alleged attack, raising concerns that any evidence the inspectors find could be useless.
Uzumcu told an emergency meeting of the organization in The Hague that Russian and Syrian officials have informed the OPCW team that there were "still pending security issues to be worked out before any deployment could take place".
Haley said during an appearance on "Face the Nation" on Sunday that Treasury Secretary Steven Mnuchin would be announcing new sanctions directed at companies associated with Syria's chemical weapons program.
Douma hospital workers who stayed in the town after the army recaptured it have said that none of the people injured on the night of the attack were exposed to chemical weapons.
Douma was the last rebel-held town near Damascus, and the target of a government offensive in February and March that killed hundreds of people and displaced tens of thousands.
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Officials said the blackout was caused when an excavator accidentally downed a transmission line, the Associated Press reported . On Wednesday, Mammoth Energy attempted to explain how the latest massive power outage occurred.
The alleged attack and subsequent military response underscored the challenge that the seven-year conflict in Syria poses for the West. President Donald Trump wants to remove US troops from Syria, where it has been fighting the Islamic State militants.
Experts from the global chemical weapons watchdog are in Syria and are now expected to visit that site in the town of Douma Wednesday. But others said it would be wiser and more effective to wait for a period longer than three days after the U.S., British and French infuriated Russian Federation with their missile strikes on Syria on Friday.
He said any use of chemical weapons is in complete disregard of humanity, and is reprehensible and contrary to the provisions of the Chemical Weapons Convention as well as accepted global norms. It also reported a separate air strike on the Dumayr air base near Damascus. Israel did not confirm or deny mounting the raid. Nuseir said a cylinder was found leaking the poison gas, adding that he didn't think it was dropped from the air because it still looked intact. He said he tried to enter the shelter but was overcome by a strong smell of chlorine and his comrades pulled him out.
As CBS News correspondent Seth Doane reports, rebel forces had held Douma nearly since the start of the war in Syria, now more than seven years old, and the government's fight to take it back was fierce.
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But this also is a trick that feels all too familiar-a bit like the Trojan horse being walked right through the gates of Troy. It's unclear if Best Buy will pay a standard commission as an Amazon merchant, or whether a different deal was negotiated.