A militia loyal to radical Shiite cleric Muqtada al-Sadr carries a grenade launcher outside a mosque in the Baghdad neighbourhood of Sadr City, Iraq, August 6.

Coalition troops battled militiamen loyal to radical Shiite cleric Muqtada al-Sadr in several Iraqi cities on Friday, the second day of fighting that has caused hundreds of casualties.

Fighting raged unabated in and around Najaf on Thursday and Friday between al-Sadr's Mahdi Army militia and US troops who were called in to support Iraqi national guardsmen.

US aircraft and helicopters pounded the city after midnight and early Friday morning as the battles concentrated around the 20th Revolution Square and Najaf vast cemetery.

The streets of the city were empty as people were forced to stay at home while the power and telephone communication lines were cut.

According to US military, about 300 Iraqis have been killed in clashes in the past two days in Najaf.

"We estimate we've killed 300 anti-Iraqi forces in the past two days of fighting," said an officer.

A total of three US troops were killed and 12 wounded in the fighting in Najaf, she added.

However, Adnan al-Zarfi, the governor of Najaf, told reporters that about 400 members of Mehdi Army were killed and some 1,000 of them were arrested in recent clashes in Najaf.

The governor on Friday issued a 24-hour ultimatum to the militia loyal to al-Sadr to leave Najaf or face a US military offensive.

"The military operations will continue unless the Mehdi Armymilitia leaves the province and I give them 24 hours to do so from the moment my words are broadcast," al-Zorfi said. In Baghdad, a total of 19 Iraqis had been killed and 111 wounded in clashes in Baghdad's Sadr City district between Shiite militiamen and Iraqi police backed by US troops since early Thursday, Iraq's Health Ministry said.

Elsewhere, four people were killed and 10 others wounded in overnight clashes between Mehdi fighters and Italian troops in the southern Iraqi city of Nasiriyah, some 375 km south of Baghdad.

Mehdi fighters launched a dozen attacks shortly after midnight with rocket-propelled grenades, mortars and small arms at Italian troops and other key facilities in the city.

Power lines were cut in the city.

An Italian military official confirmed that its troops clashed with Shiite Muslim militiamen in Nasiriyah early on Friday and tensions were still high.

Italian forces in and around Nasiriyah have fought sporadically with Mehdi militia over recent months.

About 2,700 Italian troops are based in Iraq.

Source: Xinhua