Syrian army armored vehicles have clashed with rebels in Damascus in what residents said was the heaviest fighting in the capital since the revolt against President Bashar al-Assad began 17 months ago.
The spread of hostilities into the Syrian capital comes as United Nations envoy Kofi Annan is visiting Moscow to promote a peace plan for Syria. On Tuesday, he will meet President Vladimir Putin, who has resisted Western calls to increase pressure on Assad.
Talks between Putin and Annan are not expected to break any new ground after Russian Foreign Minister Sergei Lavrov said Western attempts to threaten Syria with further sanctions amounted to blackmail.
Armored vehicles rolled into the southern Damascus district of Midan on Monday and were reinforced by security forces surrounding the area. Residents said they saw snipers deployed on rooftops.
"There are troops everywhere, I can hear ambulances," said a resident near Midan. "It feels like a war in Damascus."
A video uploaded by opposition activists aired on al-Jazeera television showed men in jeans hiding in sandbagged alleyways, firing rocket-propelled grenades and machine guns. It was the second straight day of fighting in Midan and Tadamon after major battles on Sunday.
A fighter told Reuters that the rebels could not retreat after a few hours of fighting, as they had in previous incursions into the capital, because they were surrounded by government forces.
"They want to leave. If they were able to leave they would have left," he said. "The whole area is surrounded."
The government has said little about the unrest in the capital. State television reported on Monday that security forces were chasing "terrorist groups" that had fled to some neighborhoods in Damascus.
Anti-government activists said clashes so close to the seat of government showed that rebels were chipping away at state power in a capital once seen as Assad's impenetrable stronghold.
"When you turn your guns against the heart of Damascus, on Midan, you have lost the city. The rebels in the street have the support of families across Damascus," said Damascus-based activist Imad Moaz.
Activist accounts are hard to verify because the government restricts access to international media.
"ELEMENTS OF BLACKMAIL"
The West wants Moscow to drop its support for Assad, which has seen Russia veto action against him at the U.N. Security Council. But before talks with Annan, Foreign Minister Sergei Lavrov signaled no change in Moscow's position.
Lavrov said Western efforts to pass a Security Council resolution - which would extend a U.N. monitoring mission in Syria and also include a threat of sanctions - contained "elements of blackmail". He called for support for Moscow's rival text instead, which does not call for sanctions.
"If our partners decide to block our resolution no matter what, then the U.N. mission will not have a mandate and will have to leave Syria. That would be a pity," he said.
The small, unarmed monitoring mission is the only international military presence in Syria. It was brought in as part of a peace plan backed by Annan, but suspended due to rising violence in Syria, where activists say more than 17,000 people have died.
Activists reported at least seven people killed in the fighting in Damascus on Monday, but said casualties were hard to determine due to difficulty of movement in violence-hit areas.
Video released by activists showed armored vehicles and troops in combat gear deployed on the highway from Damascus to Amman. Protesters had blocked the entrance to the highway with burning tyres to ease pressure on Midan fighters.
One activist, who asked not to be identified, said residents were braced for more trouble in the capital after the army crushed pockets of revolt in suburbs outside Damascus.
"There were thousands of fighters in some of those suburbs. Some of them were killed but a lot of them fled and they've been heading to the capital itself," the activist said.
Pressure on Assad has been growing both from outside the government and within. Morocco asked Syria's ambassador to leave, and Damascus immediately retaliated by declaring Morocco's ambassador persona non grata.
The move comes days after the Syrian ambassador to Iraq defected to the opposition, and a week after top general and Assad insider Manaf Tlas fled Syria.
What began as a protest movement inspired by demonstrations in other Arab countries has become an armed insurgency fighting back against Assad's crackdown. The International Committee for the Red Cross now classifies the conflict as a civil war.