May 6, 2007

BAGHDAD, Iraq (CNN) -- A pre-dawn coalition military raid killed at least eight gunmen and uncovered a bloodstained torture chamber in a building in Baghdad's Sadr City that was later destroyed by a powerful controlled explosion.

But throughout Sunday insurgents wreaked havoc by killing at least 45 people and wounding dozens of others in multiple bomb attacks.

The deadliest bomb attack took place in a market in southwestern Baghdad's Bayaa section around noon. An Iraqi interior ministry official said a parked car bomb explosion killed 33 people and wounded 74 others.

Insurgents frequently target busy markets to produce the most carnage. Police and government officials are also prime targets.

One police officer was killed and three others were wounded while patrolling Baghdad's Saydia neighborhood when a roadside bomb exploded, an interior ministry official said.

Earlier in the day, six police officers were killed and 10 others were wounded when a suicide car bomber exploded outside the police headquarters in Samarra, located just north of Baghdad.

A Samarra police official said the attack took place just as a curfew imposed to prevent such attacks was lifted. The curfew was immediately reimposed.

The Islamic State of Iraq -- the insurgent umbrella group that includes al Qaeda in Iraq -- had recently warned Samarra police that they would be targeted in future attacks, which prompted the curfew.

Within Baghdad's central Mansour district, at least five people were killed and 10 others were wounded in the blast from an explosives-rigged car parked near the Labor Ministry, an interior ministry official said.

U.S. and Iraqi forces chasing a "terrorist" with ties to Iran early Sunday discovered a bloodstained torture chamber and a massive amount of artillery stored in a building in Baghdad's Sadr City, the U.S. military said.

"Had that thing gone off -- when you start talking about 150 artillery shells -- the extensive damage that it could have done in killing innocent civilians in Sadr City would have been horrific," U.S. military spokesman Maj. Gen. William Caldwell said at a news conference Sunday.

The building was destroyed in a controlled explosion by a U.S. military ordnance team. Video showed a massive pile of rubble, with some debris landing on nearby cars. Other vehicles had shattered windows, possibly from the impact of the blast.

The raid took place in the pre-dawn hours of Sunday, and triggered a gunbattle that left eight to 10 gunmen dead, according to the U.S. military. There were no reports of any casualties among coalition or Iraqi security forces.

There were no reports of any casualties among coalition or Iraqi security forces.

'Secret cell'

Sadr City, a densely populated Shiite neighborhood, is a stronghold of radical Shiite cleric Muqtada al-Sadr's Mehdi Army militia.

Caldwell would not reveal specific information about the "known terrorist" that was the target of the intelligence-driven raid because he was still on the run.

"As best we know this was some kind of Shia extremist element, some sort of secret cell," Caldwell said.

Separately, the U.S. military on Sunday announced the deaths of four U.S. troops in Iraq over the past two days, which brings the number of American service members who have died in Iraq in the first three weeks of May to 14.

All but one of the deaths were combat-related.

A U.S. soldier was killed and four others were wounded when a roadside bomb exploded in western Baghdad Friday, the military said.

Two U.S. Marines were killed Saturday while conducting combat operations in the Anbar Province, the military said.

A Task Force Lightning Soldier died Sunday in a non-combat related incident, the military said.

CNN's Ingrid Formanek and Jomana Karadsheh contributed to this report.