BEIRUT | Syrian troops took positions on rooftops and gunfire crackled for hours Tuesday as pro-government gunmen attacked two villages in northeastern Syria in a move to crush a popular uprising against President Bashar Assad's authoritarian regime, witnesses said.
Syria's leading pro-democracy group, the Damascus Declaration, urged the Arab League to impose sanctions on the regime and said the death toll from more than three weeks of unrest had topped 200.
The White House joined a growing chorus of international condemnation, saying the "escalating repression by the Syrian government is outrageous."
Protests erupted in Syria more than three weeks ago and have been growing steadily, with tens of thousands of people calling for sweeping reforms. The Assad family has kept an iron grip on power for 40 years, in part by crushing dissent.
Mr. Assad has blamed the violence on armed gangs rather than reform-seekers and has vowed to crush further unrest.
He has made a series of overtures to try and appease the growing outrage, including sacking local officials and granting Syrian nationality to thousands of Kurds, a long-ostracized minority.
But the gestures have failed to satisfy protesters who are demanding political freedoms and an end to the decades-old emergency laws that give the regime a free hand to arrest people without charge.
Details on Tuesday's violence in the villages of Bayda and Beit Jnad were sketchy, but a resident from a nearby town said he heard heavy gunfire until late afternoon. From a distance, he saw troops in Bayda taking positions on rooftops.
He said residents in Bayda told him by telephone that two people were shot and wounded and dozens were detained.
Like most eyewitnesses who spoke to the Associated Press, the resident asked that his name not be used because he was afraid of government reprisals. The government has placed severe restrictions on the media and has expelled reporters, including journalists from the Associated Press.
The villages are several miles from the port city of Banias, which the army has sealed off during days of unrest. Security forces killed four protesters in Banias on Sunday.
Haitham al-Maleh, a leading Syrian opposition figure in Damascus, said residents told him that attackers were using automatic rifles in Bayda and Beit Jnad. Mr. al-Maleh said villagers have told him there were casualties in Tuesday's attack, but the reports could not be independently confirmed.
The White House on Tuesday called on Syria to respect "universal rights of the Syrian people, who are rightly demanding the basic freedoms that they have been denied."
Instability in Syria has been a blow to U.S. efforts to engage with Damascus, part of Washington's plan to peel the country away from its allegiance to Hamas and Hezbollah.
Also Tuesday, Human Rights Watch said Syrian security forces prevented medical staff from reaching the wounded in at least two towns where security forces clashed with protesters last week.
The New York-based group said security forces did not allow ambulances to approach the road to pick up the wounded after prayers Friday in the southern town of Daraa and in Harasta, near Damascus.
Friday marked the single bloodiest day of the uprising, with 37 killed around the country.