BAALBEK, Lebanon — Syrian forces loyal to President Bashar Assad have driven most rebel fighters from the town of Zabadani, northwest of Damascus, in a vicious assault that refugees reaching Lebanon's Bekaa Valley say is similar to the one that's now taking place in Homs, Syria's third largest city.

"There is no water, no electricity, no gas, no bread," said Ali, who crossed into Lebanon illegally three days ago on foot with his wife and five children. "People are trapped in their houses by snipers. Some are buried under their own houses. There are bodies in the streets, and they don't allow people to reach them."

Ali, who asked that he not be identified further out of concern for his safety, described families burying their dead under cover of night in their own yards, another echo of the fighting in Homs. He also described arrests and beatings by the military to intimidate residents, and a 3 p.m. curfew enforced by sniper fire.

A resort town with a population of about 20,000, Zabadani was billed in January as the first city to have fallen completely under the control of the anti-Assad Free Syrian Army. But that status lasted less than a month, as pro-Assad forces undertook an offensive that intensified three weeks ago, just as the offensive against Homs also was launched.

The offensive in Homs, which has been under constant bombardment for the past 20 days, claimed the lives of two journalists Wednesday, including an American who was on assignment for Britain's Sunday Times. Another 60 people also were killed in the city's Baba Amr neighborhood, according to Syrian activists.

Marie Colvin was killed when artillery and rocket fire struck the house where she was staying in Baba Amr. A French photographer, Remi Ochlik, was killed along with her. Three journalists also were wounded in the bombardment, which Syrian activists in the city said had intensified in the last 24 hours. Human Rights Watch has reported that the military is using 240 mm artillery rounds, the same as the Russian military used in its intense shelling of the Chechen city of Grozny more than a decade ago.

The intensification of the Syrian offensive in Homs and elsewhere comes ahead of two key events: a referendum on a new constitution that Assad has called for Sunday and a conference Friday in Tunisia at which representatives of 70 countries are expected to discuss whether to provide arms to the rebels.

The Homs offensive and the events in Zabadani show how crucial a decision to supply weapons and ammunition could be to the rebel forces.

Refugees say the rebels have largely withdrawn from Zabadani, and one Lebanese man who's involved in smuggling medical supplies into the town said the Free Syrian Army's supply lines had been cut.

"They ran out of ammo," he said.

Ali gave a similar assessment. "They quit 15 days ago," he said. "There are only a few left."

Shelling by army tanks and artillery increased about a month ago, said a 35-year-old resident of the city who gave her name as Umm Zabadani, a nickname that means "Mother of Zabadani," rather than her real name.

Refugees in many cases are still afraid to speak to journalists, and Lebanese activists who are helping the refugees say that Lebanese intelligence agents sympathetic to the Assad government have detained and harassed them.

"We have not been able to get anything into the city for 10 days," said a Lebanese doctor in the Bekaa who's been sending medical and humanitarian aid to Zabadani.

"The only people who are still in the city are the people who are too poor to leave," said Umm Zabadani, who said her last contact with people in the town was a week ago. "People are afraid to leave their homes."

She now shares a five-room house with 24 other people. A single stove provides heat against the snowy winter. She left a month ago, but she said that people who'd arrived in Baalbek from Zabadani on Tuesday had reported that there were still clashes between the rebels and the Syrian military.

Umm Zabadani said that others who were fleeing Zabadani had been pursued to the nearby Syrian village of Bloudan, which was shelled by tanks.

(Enders is a McClatchy special correspondent.)

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