Coalition forces under fire in Ramadi
Potentially one of the deadliest days for Americans since May 1
Is the coalition in control in Iraq? CNN's Walter Rodgers reports.
CNN's Jim Clancy on fighting in Baghdad and Fallujah.
In Najaf, protests over the treatment of a top cleric turn violent.
CNN's Bruce Morton on how images of war helped shape, even reverse, public opnion.
BAGHDAD, Iraq (CNN) -- As many as a dozen U.S. Marines were killed Tuesday in heavy fighting in the western Iraq town of Ramadi, the latest in a series of clashes with anti-coalition elements, Pentagon officials said.
The large-scale attack was mounted by suspected remnants of ousted Iraqi leader Saddam Hussein's Baath Party, officials said.
A high-ranking military source said initial reports indicated several government buildings had been seized by fewer than 100 insurgents.
The insurgents attacked a Marine position near the governor's palace.
The source said as many as 20 Marines were wounded. There also were heavy Iraqi casualties
The fighting was so intense that a Bradley fighting vehicle and an Abrams M1-A1 tank were damaged, U.S. sources said.
Ramadi, about 60 miles west of Baghdad, is part of the Sunni triangle, an area north and west of the capital where much of the resistance to the U.S.-led occupation has occurred.
The 1st Marine Expeditionary Force recently took over from the Army's 82nd Airborne Division in the region, which includes the area extending to the border with Syria.
One Pentagon official described the region as "the badlands."
East of Ramadi, heavy fighting was reported in the Sunni enclave of Fallujah as Marines and Iraqi security forces were reasserting control after the killing and mutilation of four civilian security guards last week.
And in Baghdad and at least four cities in the country's south, U.S. and coalition troops battled supporters of Shiite Muslim cleric Muqtada al-Sadr for a third day.
The Marine deaths in Ramadi and that of a soldier in a Baghdad rocket-propelled grenade attack made Tuesday one of the deadliest days for American troops in Iraq since President Bush declared the end of major combat on May 1.
Eighteen Americans were killed November 15, most of them in the collision of two Black Hawk helicopters shot down in Mosul. Sixteen U.S. troops were killed November 2 when an Army Chinook helicopter was shot down near Fallujah.
In the holy city of Najaf in southern Iraq, al-Sadr's militia was in control of government, police and spiritual sites, a coalition source said.
Al-Sadr also was busing followers into Najaf from Sadr City, a Baghdad neighborhood, according to the coalition source, who said that many members of his outlawed militia, Mehdi's Army, were from surrounding provinces.
Al-Sadr -- who is wanted on murder charges in connection with the killing of a rival last year -- reportedly has taken refuge in the Imam Ali mosque in Najaf, one of Shiite Islam's holiest shrines.
A posting on al-Sadr's Web site said he has called for a general strike.
Qais al-Khazaal, a spokesman for al-Sadr, said the young cleric wants coalition troops to withdraw from populated areas and release prisoners taken into custody in recent demonstrations.
Marines moved into Fallujah from several directions -- coming under heavy fire from insurgents -- in a second day of an operation to lock down the city.
Hospital officials in Fallujah reported at least 10 Iraqis dead and 24 injured.
Abrams tanks and infantry fighting vehicles led the Marine columns across a railway line north of the city into urban areas, where they were fired on by assault rifles and rocket-propelled grenades.
The tanks and mounted grenade launchers picked off rooftop snipers, destroying at least three houses in the process.
Marines also detained six Iraqis carrying explosives near a command post north of Fallujah, a Marine officer said. The officer said the material was intended to make homemade bombs.
Despite the widespread unrest, L. Paul Bremer, the top U.S. civilian administrator in Iraq, said there was no question coalition forces were in control of the country.
"I know if you just report on those few places, it does look chaotic," Bremer said.
"But if you travel around the country ... what you find is a bustling economy, people opening businesses right and left, unemployment has dropped."
In Baghdad, firefights continued particularly in the Shiite area of Sadr City. Reports also indicated that Italian troops were battling al-Sadr supporters in the southern city of Nasiriyah.
Iraqi Shiite supporters of Muqtada al-Sadr chant anti-U.S slogans Tuesday in Najaf.
Fighting broke out between coalition forces and al-Sadr's Mehdi Army on Saturday after the arrest of the cleric's deputy on charges in connection with Abdul Majeed al-Khoei's death April 10, 2003, outside the Imam Ali shrine in Najaf.
Twelve people were arrested last fall when an Iraqi judge issued 25 warrants in the case, including the ones for al-Sadr and his deputy, Mustafa al-Yaqoubi, coalition officials said.
Yaqoubi was arrested Saturday in Najaf and turned over to Iraqi police Monday, they said.
About 50 Iraqis were reported killed around the country in Tuesday's clashes.
Hospital sources said 36 of those were killed in battles with U.S. troops in Baghdad's Sadr City, a Shiite slum named for the rebellious cleric's assassinated father.
Bremer described al-Sadr as "a guy who has a fundamentally inappropriate view of the new Iraq."
"He believes that in the new Iraq, like in the old Iraq, power should be to the guy with guns," Bremer said. "That is an unacceptable vision for Iraq."
In Najaf, spokesman al-Khazaal said al-Sadr had "received many letters from other religious leaders" supporting him, mentioning Grand Ayatollah Ali Sistani -- the most senior Iraqi Shiite cleric.
U.S. Marines on watch in Fallujah
"Sistani said in his letter that he supported us for standing for what we believe ... but that he also thought that we should try to resolve this matter in a more calm and civil way,"al-Khazaal said.
Pentagon sources said the military would exercise caution in seeking al-Sadr in an attempt to avoid giving him more stature among radicalized Iraqis.
Pentagon officials played down reports that American troops' tours of duty in Iraq could be extended to bolster the U.S. occupation force there.
Though that is one possibility, one official said it was not under "active consideration." (Full story)
About 134,000 U.S. troops are now in Iraq, but that number is scheduled to drop to 110,000 over the next few months as part of a scheduled rotation of forces.
Other developmentsSince the start of the war last year, 624 U.S. troops have died, 434 of them in hostile action. Since May 1, 315 U.S. troops have been killed in hostile action.Britain is sending thousands of troops to Iraq to replace those already serving there, said Maj. Rachel Grimes of the Ministry of Defense. She said the move was part of a "normal" six-month rotation and would not result in an increase in the number of British troops in Iraq.
CNN's Jane Arraf, Jim Clancy, Barbara Starr, Kevin Flower, Walter Rodgers, Jamie McIntyre, Wolf Blitzer and Kianne Sadeq contributed to this report.