Fighting between coalition forces and a Shiite militia raged Friday across Iraq, after killing two Americans and wounding at least 15 U.S. troops.
The U.S. military says it has killed 300 fighters over two days.
The fighting against militiamen loyal to Shiite cleric Muqtada al-Sadr began in the holy city of Najaf and has since spread to other areas across the country, and dozens have been reported killed and wounded. Also Friday, members of al-Sadr's Mahdi Army militia seized four police stations in Amarah, 180 miles southeast of Baghdad, witnesses said.
Two U.S. Marines were killed during fighting in Najaf Province on Thursday, the scene of intense clashes with a Shiite militants, the U.S. military said Friday.
Assailants and militiamen loyal to Shiite cleric Muqtada al-Sadr wounded 15 American troops in four separate attacks in Baghdad, the U.S. command said Friday. The attacks took place over a six-hour period late Thursday.
The clashes were the worst flare-up in fighting between the two sides in months.
"`We are deeply disappointed that the Mahdi militia has brought fighting back to the good people of Sadr City," said Col. Robert "Abe" Abrams, commander of the 1st Cavalry Division's 1st Brigade Combat Team, headquartered in eastern Baghdad. "We have worked tirelessly to restore essential services to the city, and these attacks hamper our efforts."
Al-Sadr's aides blamed the United States for the latest clashes and called Friday for a return to the truce. They asked for the United Nations and Iraq's interim government to stop the violence.
"We call upon the government - that has announced that it is sovereign - to intervene to stop the American attacks," Mahmoud al-Sudani, a spokesman of al-Sadr in Baghdad, told reporters.
In other recent developments:
The Marines, from the 11th Marine Expeditionary Unit, were killed Thursday during fighting in the region, the military said. The military reported Thursday that one U.S. soldier was killed when his patrol near Najaf was attacked.
At least 921 U.S. service members have died since the beginning of military operations in Iraq in March 2003, according to the Defense Department. Of those, 681 died as a result of hostile action and 236 died of non-hostile causes.
The military had earlier reported seven U.S. soldiers wounded in violence in Baghdad on Thursday.
Some of the worst fighting was in the Baghdad neighborhood of Sadr City, where the Health Ministry said 19 people were killed and 111 wounded during fighting Thursday and early Friday between U.S. troops and al-Sadr militants. Separate attacks blamed on al-Sadr's followers wounded 15 American soldiers in Baghdad.
In Najaf, 100 miles south of Baghdad, U.S. choppers attacked militants hiding in a cemetery near the Imam Ali Shrine in the old city at Najaf's center, where smoke could be seen rising.
Gunfire and explosions rang out as U.S. soldiers and Iraqi policemen advanced toward the area, witnesses said. The streets were otherwise deserted and shops were closed.
"The area near the (Imam Ali Shrine) is being subjected to a war," said Ahmed al-Shaibany, an official with al-Sadr's office in Najaf. "Najaf is being subjected to ... total destruction," he said. "We call on the Islamic world and the civilized world to save the city."
The U.S. military has accused the militants of hiding in the shrine compound to avoid retaliation by U.S. forces. It had no comment on Friday's clashes.
A coalition base near Najaf, Camp Golf, was hit by mortar fire early Friday, while rounds fired at a base housing Ukrainian troops missed their target. A Polish military spokesman says no one was hurt.
Battles between the two sides in Najaf have killed at least 10 people and wounded 40 others, according to Hussein Hadi of Najaf General Hospital official.
In Samarra, 60 miles north of the capital, guerrillas attacked a convoy of 10 U.S. Humvees at dawn, witnesses said. U.S. helicopters fired rockets at insurgent positions, and the U.S. convoy pulled out.
Ahmed Jadou'a, an official at Samarra Hospital, said at least two people were killed and 16 injured during the fighting. Two houses were also destroyed.
In the southern city of Nasiriyah, assailants attacked Italian troops with automatic weapons, an Italian military spokesman said on condition of anonymity. They also attacked a police station, prompting the local governor to call for Italian military assistance, he said. There were no coalition casualties, the spokesman said.
The fighting, which lasted until dawn Friday, killed eight Iraqis, including five militants, and injured 13 others, according to AbdelKhuder al-Tahir, a senior Interior Ministry official.
"Today, the city is more stable. Policemen and National Guard are in control of government buildings one side of the city, while Italian forces are in control of the other side. Some of al-Sadr's followers are moving in the center of the city, but the rest of the city is under our control," he said.
Tensions were running high in the southern city of Basra, where British troops clashed Thursday with the Mahdi Army. Violence there killed five al-Sadr fighters, said As'ad al-Basri, an al-Sadr official in the city. "The clashes with the British will continue and they are going to escalate after Friday prayers," he said.