Troops have been deployed overnight in a suburb of the Syrian capital, Damascus, witnesses say.
White buses brought in hundreds of soldiers in full combat gear into Douma, a witness told Reuters news agency on Wednesday. Pro-democracy protesters have tried to march from the suburb into the centre of the capital in the last two weeks but have been dispersed by security forces.
More than 2,000 security police deployed in Douma on Tuesday, manning checkpoints and checking identity cards to arrest pro-democracy sympathizers, the witness, a former soldier, said.
He said he saw several lorries in the streets equipped with heavy machine guns and members of the plainclothes secret police carrying assault rifles. He believed the soldiers to be Republican Guards, among the units most loyal to Bashar al-Assad, the president.
Meanwhile, Syrian human rights organization Sawasiah said security forces have killed up to 35 civilians since they entered the southern city of Deraa at dawn on Monday.
Diplomats said Assad had sent the Fourth Mechanized Division, commanded by his brother Maher, into the city.
Death toll mounting
Late on Tuesday, the state news agency SANA reported the army "continued to chase armed groups and extremists in Deraa who attacked military positions, cut off roads and forced passers-by to stop so they could hit them."
Sawasiah said electricity, water and telecommunications was cut in Deraa and that tanks were firing at residential buildings, with supplies blood at hospitals starting to run low.
In the coastal city of Baniyas, thousands took to the streets on Tuesday, chanting "freedom, freedom," amid reports that the army had been deployed in the surrounding area.
At least 400 civilians have been killed by security forces since mid-March in their campaign to crush the protests, Sawasiah said, adding that the United Nations Security Council must convene to start proceedings against Syrian officials in the International Criminal Court and "rein in the security apparatus".
The UN secretary-general has called for an independent inquiry into the deaths of people he has described as peaceful demonstrators.
But Syria's UN envoy said the country is perfectly capable of conducting its own transparent inquiry into the deaths.
International pressure on Assad is mounting, with European governments urging Syria to end the violence and the US saying it was studying more targeted sanctions against the country.
PHOTO CAPTION
A tank in Daraa where a deadly crackdown against pro-democracy protesters raged into a second day, activists said, as Washington considered "targeted sanctions" against Damascus.
Al-Jazeera