The government, trying to pacify the country before elections in January, has vowed to restore state authority in rebel bastions such as the Sunni Muslim city of Falluja, if necessary by force.

A rocket or mortar attack in the compound of the Ibn al-Bitar hospital in central Baghdad killed one person and wounded five, witnesses and hospital officials said.

A rocket struck the car park of the Mansour Melia hotel, where some foreign news organisations are based, damaging vehicles but causing no casualties.

Five churches were hit in a string of bomb attacks before dawn that were apparently meant to intimidate Iraq's small but deep-rooted Christian community, already shaken by a deadlier series of bombings of churches that killed 11 people in August.

A nightwatchman was jolted out of bed to find the St Rum church in the central Karrada district had been gutted, its pulpit and pews reduced to ashes.

"This is no good. We live in fear," said Marlene Mikhail, 40, sitting in her home with crosses and icons on the walls.

Iraq's estimated 650,000 Christians make up about three percent of the population. Most are Chaldeans, Assyrians and Catholics.

The US military has accused its top enemy in Iraq, Jordanian militant Abu Musab al-Zarqawi, of carrying out bombings aimed at fueling sectarian strife and civil war.

US forces have intensified air strikes on suspected Zarqawi bases in Falluja, saying these are part of a drive to thwart attacks in Iraq during the Muslim holy month of Ramadan.

Zarqawi's group claimed responsibility for twin suicide bombings that killed five people, including three Americans, inside Baghdad's fortified Green Zone on Thursday.

Those bombings have reinforced UN fears about sending more senior staff to Iraq to help prepare for the elections, a spokesman at UN headquarters in New York said.

The UN pulled all international staff out of Iraq last year after two bomb attacks on UN headquarters in Baghdad, and now keeps no more than 35 staffers in the country.

Interim Prime Minister Iyad Allawi threatened on Wednesday to attack Falluja unless its people handed over militants loyal to Zarqawi. City notables who had been in peace talks with the government deny knowledge of the Jordanian's network.

US forces detained chief Falluja negotiator Khaled al-Jumaili on Friday, police in the rebel-held town said.

British troops could move nearer Baghdad to cover for US soldiers fighting in Falluja and elsewhere, British media said on Saturday. It would be the first time British troops have operated outside the relatively quiet Basra area in the south.

Up to 650 troops would be involved in the move, which would be meant to last for just a few weeks, the BBC said.

A Ministry of Defense spokesman in London said no decision had been made.

Meanwhile, three US soldiers, a marine and a civilian translator were killed and one soldier wounded in two car bombings in Iraq, one to the west and another in the northern city of Mosul, the military said yesterday.

A suicide car bomber blew himself up on Friday afternoon near to an American Humvee that formed part of a patrol near the city of Qaim on Iraq's border with Syria, said marine spokesman Lieutenent Lyle Gilbert.

"There were four dead -- one marine, two soldiers and one civilian translator," Gilbert told AFP. He was unable to give the nationality of the translator.

Less than four hours earlier, at about 1:20 pm (1020 GMT), a car bomb exploded on a military convoy travelling through central Mosul, 370 kilometres (230 miles) north of Baghdad, the military said.

"One soldier assigned to Task Force Olympia died of wounds following a car bomb attack," a statement said.

The deaths raise to 1,087 the number of US soldiers killed in Iraq since the US-led invasion in March 2003, according to an official Pentagon tally.

An Iraqi press photographer working for a European agency was shot dead outside his home in the northern Iraqi city of Mosul, the second Iraqi journalist to be murder in Iraq in the past week, media rights group Reporters Without Borders (RSF) said yesterday.

Karam Hussein, who worked for the European Press Agency, was approached by four masked men who shot him and then fled, RSF said.

Hussein has been with EPA for just three months and previously worked for the US press agency Associated Press.

On Thursday a female journalist with the Kurdish television company Al-Hurriya, Dina Mohammed Hassan, was killed in the Iraqi capital Baghdad.

Their deaths bring the total number of journalists and other media workers killed in Iraq since the beginning of the US-led invasion to 44, according to Paris-based RSF.