The commander of the U.S. Army's 82nd Airborne Division, Major General Charles Swannack, says several thousand Ramadi-based troops may be withdrawn from the town as early as January.

Ramadi lies in the heart of the Sunni triangle, a pro-Saddam Hussein, Sunni Muslim-dominated area north and west of Baghdad, where U.S. troops have come under daily fire for months.

General Swannack, who has 20,000 soldiers in the region, said the decision to hand over security responsibilities to the Iraqis in Ramadi was based on his assessment of the police force that his troops have been training. "The police are doing a credible job. We still need to continue training them. But I believe our joint operations between now and the first of January will allow us to move to the second stage in regard to security for Ar-Ramadi, the town," he said.

In the second stage, U.S. forces would stay outside of town and leave policing duties to the Iraqis. Troops would only intervene if the police ask for assistance.

The plan appears to be in line with Washington's effort to transfer power to a transitional Iraqi government by June.

Meanwhile, the effort to restore security continues.

In Baghdad, a barrage of explosions from heavy weapons jolted residents for several hours after sunset on Tuesday.

A U.S. military spokesman says the explosions were part of Operation Iron Hammer, one of several combat operations the military has launched in recent days to root out guerrilla fighters. An upsurge in attacks against coalition forces has killed more than 80 U.S. soldiers this month.

In the towns of Baqubah and Samara, north of Baghdad, U.S. jets, attack helicopters, and tanks pounded suspected insurgent sites on Tuesday as part of the effort.

The U.S. military says such offensive operations will continue as long as they are necessary to stop the attacks.

Critics say the overwhelming military display is frightening and is alienating ordinary Iraqis. But Major General Swannack defended the military's use of heavy weapons in urban areas. "I think it demonstrates our resolve. When we positively identify an enemy target, we're going to take it out with every means available," he said.