Battles at Najaf

US tanks swept into Iraq's holy cities of Najaf and Kerbala yesterday, pounding and killing fighters loyal to Shi'ite Muslim cleric Moqtada al-Sadr.

After days of cat-and-mouse skirmishes across southern Iraq and spurred by growing anger against him among rival Shi'ite leaders, troops pounced on key buildings to tighten a squeeze on Sadr, who has taken refuge among Najaf's ancient mosques.

American soldiers, whose commanders said they killed more than 40 fighters, secured the local governor's mansion in Najaf.

At the same time, US Iraq administrator Paul Bremer was appointing a new man to run the city and calling on Sadr to give himself up to face charges for the murder of a fellow cleric.

"This does not signal the beginning of a new offensive," a senior US military official told Reuters. "However, we are prepared to continue steadily going after Sadr and his militia, to continue to keep up pressure on them, until we have Najaf completely back in our hands."

Some success in quelling Sadr's month-old insurgency, with tacit approval from Iraqis likely to be part of an interim government from July, is better news for US forces after anger at their treatment of Iraqi detainees in military prisons.

After irritating Arabs with earlier comments, US President George W. Bush apologised.

After meeting Jordan's King Abdullah, he said: "I told him I was sorry for the humiliation suffered by the Iraqi prisoners and the humiliation suffered by their families".

He also defended Donald Rumsfeld, the US defence secretary whom some critics have said should resign over the affair.

There were also no reports of deaths among US troops, who have taken mounting casualties lately. At least 18 have been killed so far this month, including one in a suicide car bombing in Baghdad yesterday that also killed five Iraqis.

April was the bloodiest of 13 months of war with 129 killed.

Troops killed 41 of Sadr's Mehdi Army militia at Kufa, near Najaf, after drawing them into the open, a senior US military official told Reuters. The basis of the number was unclear.

Six more guerillas died when US armour moved into the centre of Kerbala and destroyed a Sadr office before withdrawing.

US troops steered clear of Najaf's shrines but briefly posted tanks near those in Kerbala, where they had ousted Sadr's forces from several buildings over the past few days.

Italian troops also clashed with Sadr's militiamen, engaging in a short gunbattle south of Nassiriya, Italian officials said.

Tanks surrounded the governor's house in Najaf, five kilometres from shrines that are the focus of million-strong pilgrimages among Shi'ites from Iraq, Iran and across the world.