Beirut: Syrian forces killed at least 25 people, arrested scores of others and torched more than 100 homes while seizing a northern city from rebels, activists said on Friday.
The violence followed the highest level defection yet from the regime of President Bashar Assad and came while the US and others called for new global efforts to push him from power.
Anti-regime activists inside Syria cited the fresh violence in dismissing the Paris meeting of the "Friends of Syria."
"I don't expect anything to come out of it, like all the other meetings," said Osama Kayal of the city of Khan Sheikhoun in north Syria. "We're sick of meetings and deadlines. We want action on the ground."
The deadly government raid on Khan Sheikhoun, a city of 80,000 along Syria's main north-south highway, showed a new determination by the regime to retake rebel-held areas.
During a visit to the city last month, an Associated Press reporter found rebels able to move freely, though the government often fired on them from a central base and a number of checkpoints on the city's edges.
Local rebels said they didn't have the firepower to face the army, but they would often attack army convoys on the highway with rocket-propelled grenades.
Kayal said Friday that government forces tried to retake the city early this week, but local fighters repelled them, destroying at least six army vehicles a killing the soldiers riding in them.
But the rebels withdrew on Wednesday when a larger force arrived, backed by attack helicopters that the rebels had no way of countering. Once inside the city, the troops set homes on fire and arrested dozens of people, Kayal said.
He said he knew of 25 people who had been killed since Wednesday. He spoke via Skype from a nearby village.
"I had to leave the city because they burned down my house," he said.
Another activist, Fadi al-Yassin, said via Skype that he had the names of 30 dead, but that many more could still be inside the city.
"It is very hard to know how many there are, because the city is now completely under the army's control," he said, adding that soldiers detained hundreds of residents and set fire to more than 100 homes.
The government offensive in Khan Sheikhoun appeared to be part of a push to seize control of the highway.
The Britain-based Syrian Observatory for Human Rights reported clashes between rebels and regime troops in Maaret al-Noman, another city on the highway to the north. Two rebels and two civilians were killed in government shelling, it said, while rebels killed at least eight soldiers in an attack on a military vehicle.
The group, which relies on a network of activists inside Syria, reported shelling attacks and clashes elsewhere in the country, saying at least 38 civilians and 14 government soldiers were killed.
Activist claims could not be independently verified. The Syrian government bars most reporters from working freely in the country.
It blames the uprising on armed gangs seeking to weaken the country.
In Paris, the US and its partners called for pressure on Russia and China to force Assad to step down. Those two countries have stood by Assad and protected him from sanctions by the U.N. Security Council.
At the conference, French Foreign Minister Laurent Fabius announced the defection of Brig. Gen. Manaf Tlass, a member of the elite Republican Guard and a son of a former defense minister.
He is the uprising's highest ranking defector yet, marking a blow to a regime that has largely held together in the face of the uprising.