Rebels with the al-Nusra Front group seized the town of Maaloula Saturday night, CNN reported. The town is about an hour outside of Damascus.
"We cleansed Maaloula from all the Assad dogs and all his thugs," a rebel commander is heard saying in a video posted on YouTube after the town fell to rebel fighters.
It was not clear what would happen to the town's Christian inhabitants, some of whom fear radical Islamists among the rebels' ranks, CNN said.
The U.S. military is preparing for three days of attacks on Syria -- longer than originally planned, the Los Angeles Times reported.
Two military sources told the Times the Pentagon had greatly expanded its list of 50 targets.
"There will be several volleys and an assessment after each volley, but all within 72 hours and a clear indication when we are done," said an unnamed officer familiar with the planning.
President Obama, who is seeking congressional approval before launching strikes to punish the Assad regime for its alleged use of chemical weapons in violation of international standards, and his aides have been busy mounting a campaign to raise support for U.S. efforts in Syria.
"Failing to respond to this outrageous attack would increase the risk that chemical weapons could be used again, that they would fall into the hands of terrorists who might use them against us, and it would send a horrible signal to other nations that there would be no consequences for their use of these weapons," Obama said in his weekly radio address Saturday.
The Syrian Network for Human Rights Sunday said nearly 3,000 people had died after being tortured since the start of the now 18-month civil war.
The SNHR said the victims included 87 children, 27 women, and 124 Syrian Free Army soldiers. About 95 percent of the victims were civilians.