Iraqi forces fought militants loyal to Shia cleric Moqtada al-Sadr today in the second day of a campaign the government hopes will end militia control without the help of foreign troops.
A resident carries an injured boy in Baghdad's Sadr City
The fighting centred on the southern oil-rich city of Basra but has spread to Baghdad and other towns and has killed more than 60 people and wounded hundreds.
The sounds of gunfire and explosions could be heard echoing throughout Basra today as Iraqi security forces fought their biggest military campaign without US or British troops.
Prime Minister Nuri al-Maliki, in Basra to oversee the military operation, said fighters would be spared if they surrendered within 72 hours.
Sadr, an anti-American cleric, helped install Mr Maliki in power after an election in 2005 but later broke with him. He won praise from Washington for declaring a ceasefire last August, but that truce appears to be disintegrating.
His followers have begun a disobedience campaign, ordering shops, universities and schools to shut down, and he has threatened a "civil revolt" if attacks continue.
The worst fighting was in Basra, where a health official said 40 people had been killed and 200 wounded. The city, like much of the Shia south, has seen turf wars between Sadr's followers and those of rival Shia groups.
In the capital, a health official said 14 people were killed and more than 140 wounded in clashes in Sadr City, the Shia slum named for the cleric's slain father, where the younger Sadr and his Mehdi Army militia have widespread influence.
Three US civilians were seriously hurt in a mortar attack on the Green Zone diplomatic and government compound, the US embassy said. A column of black smoke was visible over the zone, which has been hit repeatedly by mortars and rockets for days. In other parts of the capital, police said three people were killed in the Karrada neighbourhood and four in Risala.
Sadr fighters seized control of seven districts in the southern town of Kut.
Basra police said heavy gunbattles restarted early today in five districts of Basra after a brief lull. Mortars or rocket attacks regularly struck Iraqi security checkpoints and bases.
Ground commander Major-General Ali Zaidan said his forces had killed more than 30 militants on the first day of the operation, which began before dawn on Tuesday. More than 25 were wounded and around 50 were captured, he said.
British forces, which patrolled Basra for nearly five years, have withdrawn to a base outside the city since December and were not involved in the fighting. US forces also appeared to play little role in the clashes in Baghdad.
Washington aims to bring 20,000 of its 160,000 troops home by July after a build-up of troops reduced violence dramatically last year. But violence has increased in the past few months. Mr Maliki's government is under pressure to show it can maintain security on its own.