BAGHDAD - Three suspected insurgents fled a jail in the western city of Ramadi yesterday after overpowering guards, Iraqi officials said. The jailbreak led to a gunfight in which six policemen and seven suspected insurgents were killed, authorities said.

Iraqi security forces hunted for the three escapees, who included a top leader of the Sunni insurgent group al-Qaeda in Iraq.

The jailbreak comes as U.S. officials are shutting down their detention facilities across Iraq and as U.S. troops are sharply reducing their presence in Anbar province, a predominantly Sunni territory that was the cradle of the insurgency. Ramadi is the capital of Anbar.

The incident occurred at 3:30 a.m. as guards were escorting a group of inmates from an interrogation room to a cell, said Maj. Gen. Tariq al-Duleimiy, the Ramadi police chief.

He said a suspected insurgent told authorities that the operation had been planned.

"The plan was to grab a weapon from the guards" to flee, he said.

Lt. Col. Abdul Ghani al-Duleimiy, chief of the jail, was among those killed in the shootout, Iraqi officials said.

Iraqi officials imposed a curfew in Ramadi, limiting vehicle and pedestrian traffic as they searched for the suspected insurgents, who were believed to have fled on foot.

The police chief said Iraqi and U.S. troops had fanned out across the area to look for the men in neighborhoods and orchards.