SEVEN American soldiers were killed and more than 24 were wounded in bitter fighting with Shia Muslims in Baghdad last night in a worrying new front for coalition troops trying to stabilise Iraq.

It brought to nine the number of coalition soldiers killed yesterday in fighting with Shias loyal to Hojatoleslam Moqtada al-Sadr, a radical Shia cleric, in cities across Iraq. At least 20 Iraqis died in the clashes.

The fighting erupted during massive protests against the arrest of an aide to the anti-coalition cleric and the closure of one of his newspapers. Shia militiamen belonging to Hojatoleslam al-Sadr’s banned el-Mehdi Army tried to take control of police stations and government buildings in three districts of Sadr City, an impoverished Shia suburb in the east of Baghdad.

When American soldiers retaliated, they came under heavy bombardment from small arms fire and rocket- propelled grenades. Two loud explosions were heard in the area as the two sides traded fire. A coalition statement claimed that US forces had regained control of the buildings.

A witness to the fighting described seeing two Humvee military vehicles burning in the neighbourhood, and said that some American soldiers had taken refuge in a building. A column of American tanks was seen moving through the centre of Baghdad late last night, possibly heading towards the fighting.

Hours earlier, 22 people were killed and more than 200 wounded in a major gun battle in Najaf, when supporters of Hojatoleslam al-Sadr attacked a coalition garrison. British troops also killed four demonstrators in similar clashes in the southern city of Amara.

The violence drew sharp condemnation from coalition leaders, who were already facing a resilient Sunni insurgency and wanted to avoid clashing with the Shia majority. Last night Grand Ayatollah Ali al-Sistani, the Shias’ spiritual leader, called for calm.

In Najaf, about 5,000 supporters of Hojatoleslam al-Sadr gathered outside a Spanish-run coalition base to demand that the United States-led occupation authorities reopen the newspaper run by Hojatoleslam al-Sadr, which had been shut down last week for inciting violence against the coalition. They were also angered at the coalition’s arrest of Mustapha Yacoubi, one of the cleric’s aides.

Some witnesses said that the coalition troops had opened fire after demonstrators threw stones at a military vehicle at the entrance to the base. At least one said that armed members of the crowd — many of them in the black shirts and trousers of the el-Mehdi Army — shot at the camp on the road to Kufa, a town close to Najaf where al-Sadr lives.

During the three-hour firefight that followed, young Iraqi gunmen could be seen running and sniping from broken ground in an industrial area close to the base, while groups of men carried wounded comrades from the fighting as Apache helicopters swooped overhead. Spanish-led troops fired from their fortifications, catching dozens of people in the crossfire.

“I was standing next to the tree and then I felt fire in my leg and I fell to the ground,” one unarmed protester, who was shot in the leg, said. Hospital officials said that 20 Iraqi demonstrators had been killed and more than 200 people wounded in the clashes. One US soldier, and one Salvadoran soldier were killed. Fourteen more Salvadorans were injured.

The clash was the most deadly yet between coalition troops and Shia militiamen, and came as American forces are struggling to stamp out a Sunni insurgency in the desert west of Baghdad, where four US contractors were killed and mutilated last week in a mob rampage. Two US Marines were killed yesterday in separate attacks in the Sunni Triangle, while a car bomb in the northern oil city of Kirkuk killed three Iraqis in an attack apparently targeting an American army convoy.

Paul Bremer, the US chief administrator in Iraq, strongly condemned the fighting, as a potential new front yawned open just three months before he turns over authority to an interim Iraqi government. Iraq also faces remorseless attacks by foreign-led terrorist groups.

“This morning, a group of people in Najaf have crossed the line, and have moved to violence. This will not be tolerated,” Mr Bremer said.

Hojatoleslam al-Sadr, 30, opposes the US-led occupation of Iraq. He is at odds with most Shias, who hope to gain substantial power in the new Iraqi government, which is due to take power on June 30. Shias comprise about 60 per cent of Iraq’s 25 million people.

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