U.S. and Iraqi forces raided a Kufa (search) mosque Sunday where they said insurgents stored weapons, and the military said at least 32 fighters loyal to a radical Shiite cleric were killed during the first American incursion into the holy city.

U.S. troops also clashed with militiamen loyal to cleric Muqtada al-Sadr (search) in a Shiite district of Baghdad and in Najaf, Kufa's twin city. Nine U.S. soldiers were wounded Sunday around Baghdad, the military said, including four injured in a mortar attack in the east of the capital.

In another holy city, Karbala (search), militia fighters appeared to have abandoned their positions after weeks of combat.

A U.S. Marine was killed and several other troops were injured when a bomb hidden in a parked car exploded as two American convoys passed by near Fallujah (search), the military said.

American tanks and troops moved into the heart of Kufa, a stronghold of al-Sadr, for the first time since the fiercely anti-U.S. cleric launched an uprising against the coalition early last month. Al-Sadr, sought for the April 2003 killing of a moderate rival cleric, has taken refuge in Najaf and routinely delivers a Friday sermon in Kufa.

U.S. soldiers fought militiamen near Kufa's Sahla mosque and then raided it for weapons after an Iraqi counterterrorism force "cleared" the site, the military said. Soldiers seized a machine gun, two mortar tubes and more than 200 mortar rounds, along with rocket-propelled grenade launchers and rounds, according to a statement.

American troops smashed the gate to the mosque complex with an armored vehicle and killed people inside, mosque employee Radhi Mohammed said. An Associated Press photographer saw bloodstains on the ground indicating that someone was dragged for at least 10 yards. There also was blood in mosque bathrooms.

The fighting around Shiite holy cities south of Baghdad, among the world's most sacred Shia sites, has enraged Shiite communities in Iran and elsewhere.

In Tehran, Iranian Foreign Ministry spokesman Hamid Reza Asefi said Iran sent a "warning" message to the United States through the Swiss Embassy concerning American actions in Iraq. Switzerland looks after American interests in Iran. Asefi did not say whether the warning involved military actions around the holy cities.

"There were American forces in that local mosque last night," said Maj. David Gercken, spokesman for the 1st Armored Division. "They went in after the Iraqi forces."

Sheik Mansoor al-Asadi, head of the central council of tribes in the Najaf area, said he was "astonished" by the Kufa raid, saying it undermined efforts by local leaders to resolve the standoff between al-Sadr and the coalition peacefully.

Salama al-Khafaji, a Shiite member of the Iraqi Governing Council, denounced the U.S. move against the mosque as a "violation of sanctity" that will put an added burden on Iraqi authorities who work with the Americans.

But Maj. Gen. Martin Dempsey, commander of the 1st Armored Division, said U.S. forces took care not to damage Shiite Muslim shrines even though militiamen used them as fighting positions.

"We have no intention of entering the shrines," Dempsey said, adding that Iraqi security forces would enter them if necessary.

Al-Sadr's supporters have accused the military of desecrating holy places.

American troops also fought his militia, known as the al-Mahdi Army, around Kufa's technical college and a building known as Saddam's Palace, the military said. Thirty-two militiamen died, it said.

Medical personnel at the city's Furat al-Awsat hospital said at least 10 people were killed and 11 were wounded, however, and it was unclear whether those numbers included the fighters or referred to civilians. No U.S. casualties were reported.

Resident Mohammed Abdul-Kareem said the dead included three civilians whose houses were damaged in the fighting, which lasted from 10 p.m. Saturday until 6 a.m. Sunday.

Sixteen people also were wounded in clashes between U.S. forces and al-Sadr loyalists in Najaf on Sunday, according to hospital officials and witnesses. Two other militiamen were wounded when three projectiles exploded in central Najaf.

In Karbala, no al-Sadr fighters or American forces were seen on the streets Sunday, but the U.S. military denied claims by al-Sadr's office that all combatants agreed to withdraw from the city.

"There was no cease-fire, no deal made in Karbala," Gercken said. "We do not and will not make deals with militias or criminals."

U.S. forces captured 10 militiamen overnight in Karbala but encountered little resistance during patrols, Gercken said.

Iraqi leaders in Karbala were trying to negotiate an end to the fighting, but coalition officials have demanded that al-Sadr disband his militia and "face justice" on the arrest warrant.

"There is no presence of armed militias in the city," said Adham Mahmoud, a Karbala hotel worker. "People have started leaving their homes and going into the streets. Some have started rebuilding their damaged houses."

No insurgents were seen around Karbala's Imam Hussein shrine, one of Shia Islam's holiest sites. It was guarded by a special security force in civilian clothing that was appointed by top Shiite clerics.

"Iraqi security forces are already patrolling the city," a U.S. military statement said.

The U.S. military command denied a Washington Post report Sunday that the top American general in Iraq, Lt. Gen. Ricardo S. Sanchez, was present during some interrogations at the Abu Ghraib prison and witnessed some abuses of Iraqi inmates.

"This report is false," the U.S. military said in a statement.

Sanchez stands by his testimony before congressional committees that he was unaware of the abuses until ordering an investigation into the allegations in January, the military said.

Gunmen killed a police captain and a university student and wounded a police sergeant in Baqouba, north of Baghdad, a hospital official said. Capt. Haidar Hadi and the sergeant were giving the student a lift to Baghdad when the gunmen opened fire, said Nassir Jawad of Baqouba General Hospital.

Also Sunday, a policeman was killed and two others seriously wounded by a bomb while patrolling between Basra and Zubeir in southern Iraq, police said.