The bombing was the latest in a series of attacks across northern Iraq in recent days that have tested the capabilities of Iraq's U.S.-trained security forces.

On Sunday, Iraqi authorities in Mosul, 225 miles northwest of Baghdad, lifted a partial curfew that was imposed two days earlier in the eastern part of the city after police repulsed a series of insurgent attacks in which a police colonel was killed.

The Defense Ministry said security forces had arrested 62 people in a crackdown across northern Iraq after the street battles.

Iraqi authorities were heartened by the performance of the Mosul police, who stood their ground and drove off the insurgents.

In November 2004, Mosul's entire 5,500-member police force fled during an insurgent uprising and the U.S. military had to send American troops and Kurdish fighters to regain control of the city, Iraq's third largest.

Also Sunday, several U.S. Marines were wounded and a few vehicles were destroyed by a suicide car bombing in Anbar province, the U.S. military said without further details. Iraqi police said the attack was in Fallujah, a heavily guarded city 40 miles west of Baghdad.

Gunmen in Samarra, about 60 miles north of Baghdad, ambushed a convoy of Iraqi trucks, killing two drivers and setting their vehicles on fire, police Capt. Laith Mohammed said.

A sniper killed a government security guard in southern Baghdad, police said. Gunmen in Fallujah killed a Sunni preacher, Sheik Ali Hussein al-Jumaili, when he resisted what appeared to have been a kidnap attempt, police said.

Police found the bodies of five men in Baghdad and one in the southeastern city of Amarah. All had been shot, police said.

A U.S. military statement said coalition forces killed one man during a raid north of Beiji, 155 miles north of Baghdad.

In the Kurdish province of Sulaimaniyah, security forces fired warning shots to disperse hundreds of demonstrators who burned tires and blocked roads to protest high fuel prices and poor living conditions. Three people were injured in the protest in the town of Chamchamal.

Police Lt. Col. Ahmed Nadir said the protest began peacefully, but then some demonstrators hurled stones, burned tires and attacked shops. Witnesses said the protesters were angry over fuel shortages, high prices and frequent electricity outages.

"This is too much. We demand the regional government improve the services in Chamchamal," said Ahmed Mohammed, 18, a taxi driver "This is not the first time that we have complained. We started more than a year ago but there is no solution."