Iraqi city under curfew after attacks

BAGHDAD, Iraq (CNN) -- The Iraqi city of Samarra was under curfew Friday, a day after gunmen in more than 50 vehicles attacked police stations and checkpoints in the area, police said.

Samarra police had to call in U.S. air support to help fight the insurgents.

The clashes went on for about four hours, killing at least three gunmen and three civilians and wounding six civilians.

There were Iraqi police casualties, but authorities did not release any details.

Police said the gunmen were members of the al Qaeda in Iraq-led umbrella group Islamic State of Iraq and included foreign Arab fighters along with Iraqis.

Samarra is in Salaheddin province, about 60 miles (97 kilometers) north of Baghdad, where U.S. and Iraqi troops have stepped up operations against insurgents.

Meanwhile, U.S. troops and insurgents fought early Friday in a western Baghdad neighborhood, but there were conflicting reports on what happened.

The Iraqi Interior Ministry said a firefight broke out when ground troops, backed by helicopters, attempted to apprehend "several wanted persons."

At least 10 civilians, including women and children, were killed and 15 were wounded in a two-hour battle, the ministry.

The U.S. military had a different account.

Citing initial reports, the military said an American patrol "was engaged by small-arms fire" in the Shula area, resulting in eight "enemy" deaths.

The military didn't mention any civilian deaths, saying, "As more information becomes available, we will provide it."

Other developments

U.S.-led coalition forces killed seven insurgents and detained 12 others in raids Friday targeting an al Qaeda in Iraq cell, the U.S. military said. The raids took place east of Tarmiya, in Mosul, near Taji and in Baiji.

A U.S. soldier was killed and four others were wounded Friday by an explosion during operations in Salaheddin province, the U.S. military said. They were members of the Army's Task Force Lightning. Since the start of the war, 3,719 U.S. troops have died in Iraq, according to Pentagon figures. Seven civilian Defense Department employees also have been killed.

The U.S. military said it is investigating the death of a security detainee at a military prison in Baghdad. Preliminary medical tests indicate the prisoner died Thursday of acute renal failure.

A powerhouse Republican lobbying firm with close ties to the White House has begun a public campaign to undermine the government of Iraqi Prime Minister Nuri al-Maliki, CNN has confirmed. The firm is promoting former interim Iraqi Prime Minister Ayad Allawi, its client, as an alternative to al-Maliki. A Bush administration official said the White House has "absolutely no involvement" in the campaign. Watch why Iraq's prime minister is taking heat »

Republican Sen. John Warner of Virginia, former head of the Senate Armed Services Committee, urged President Bush on Thursday to start bringing U.S. troops home from Iraq next month. He said withdrawing some U.S. troops could prompt Iraqi leaders to action.

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CNN's Jomana Karadsheh and Raja Razek contributed to the report.

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