BASRA, Iraq - Iraqi forces fought militants loyal to Shi'ite cleric Moqtada Al-Sadr Wednesday on the second day of a campaign the government hopes will end militia control without the help of foreign troops.

The fighting centered 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 yesterday 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, a young, anti-American cleric, helped install 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 launched 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 Shi'ite south, has seen turf wars between Sadr's followers and those of rival Shi'ite groups.

In the capital, a health official said 14 people were killed and more than 140 wounded in clashes in Sadr City, the Shi'ite slum named for the cleric's slain father, where the younger Sadr and his Mehdi Army militia have wide spread influence.

Basra police said heavy gun battles restarted early yesterday 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 told Reuters 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.

"The operation is still going on and will not stop until it achieves its objectives," he said. "It is on the same scale as yesterday. "

British forces, which patrolled Basra for nearly five years, withdrew to a base outside the city in 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.

Maliki's government is under pressure to show it can maintain security on its own. US Democratic candidates who hope to succeed President George W. Bush next January are calling for a speedy withdrawal from an unpopular war.

Sadr, an influential leader who has not been seen in public for months, issued a statement on Tuesday calling on Iraqis to stage sit-ins all over Iraq and said he would declare "civil revolt" if attacks by US and Iraqi forces continued.

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