A British soldier takes a combat position during a patrol in the southern city of Basra. The violence in the war-torn capital Baghdad provided a grim backdrop to an unannounced visit by British Prime Minister Tony Blair, who flew in to offer support to his beleaguered Iraqi counterpart Nuri al-Maliki. [AFP]

BAGHDAD, Iraq - A bomb killed three American soldiers and wounded another northwest of Baghdad on Tuesday, bringing the total US military death toll in Iraq to at least 2,978 - five more than the number killed in September 11, 2001, attacks in the United States.

"The patrol was conducting a route clearance mission when a roadside bomb exploded near them," the military said.

"The joint patrol was conducting security operations in order to stop terrorists from placing roadside bombs in the area," the military said in a statement on the latest deaths. "As they conducted their mission, a roadside bomb exploded near one of their vehicles."

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Another soldier was wounded in the explosion, the military said.

Earlier Monday, the US command announced the deaths of two other soldiers and a Marine. It said one soldier died and two were wounded when a roadside bomb exploded near a US military vehicle in southern Baghdad on Monday.

An American soldier and a Marine died Sunday from combat wounds suffered in Anbar province, the military said.

Prior to the latest deaths, the AP count was 15 higher than the Defense Department's tally, last updated Friday at 10 a.m. EST. At least 2,377 died as a result of hostile action, according to the military's numbers.

The British military has reported 126 deaths; Italy, 33; Ukraine, 18; Poland, 18; Bulgaria, 13; Spain, 11; Denmark, six; El Salvador, five; Slovakia, four; Estonia, Netherlands, Thailand, two each; and Australia, Hungary, Kazakhstan, Latvia, Romania, one death each.

On Monday, British soldiers backed by tanks raided a police station in the southern city of Basra, killing seven gunmen in an effort to stop renegade Iraqi officers from executing their prisoners, the British military said.

After the British stormed the Basra police station, they removed the prisoners, who showed evidence of torture, then evacuated the building before blowing it up.

The operation showed how closely aligned some police units are with militias and death squads - and the challenges coalition forces face as they transfer authority for security to Iraqis.

In Baghdad, police found 40 bodies, apparent victims of sectarian violence. A car bomb exploded beside a market and a suicide bomber struck a bus in separate attacks that killed 14 civilians and wounded at least 33.

In the Basra raid, the British set out to arrest officers with the station's serious crimes unit who were suspected of involvement with Shiite death squads. Seven members of the rogue police unit were apprehended three days ago in other raids, said a British spokeswoman, Royal Navy Lt. Jenny Saleh.

"We had intelligence to indicate that the serious crimes unit would execute its prisoners in the coming days, so we decided to intervene," Saleh said.

British troops were fired on as they approached the station and their return fire killed seven gunmen, said Maj. Charlie Burbridge, another British military spokesman.

British and Iraqi forces transferred all 76 prisoners at the station to another facility in downtown Basra, he said. Some prisoners had "classic torture injuries" such as crushed hands and feet, cigarette and electrical burns and gunshot wounds in the knees, Burbridge said.

The British demolished the building in an effort to disband the unit. "We identified the serious crimes unit as, frankly, too far gone," Burbridge said. "We just had to get rid of it."

The unit's members, he alleged, were involved in tribal and political feuds in southern Iraq, which is mostly Shiite. They were not, he said, engaged in the kind of sectarian reprisal killings that have terrorized mixed neighborhoods of Baghdad.

Most of Britain's 7,200 troops in Iraq are based in the Basra area.

Mohammed al-Askari, a spokesman for Iraq's Defense Ministry, said the operation was coordinated with the Iraqi government. "Multinational forces got approval for this raid from this ministry and with participation of the Iraqi army," he said.

US Army Lt. Gen. Martin Dempsey, who is in charge of training Iraqi forces, said in Washington last week that efforts were under way to weed out Iraqi national police believed to be sympathetic to the militias.
Up to a quarter are thought to be aligned with the militias, which are engaged in sectarian violence.
The establishment of a viable Iraqi police force is vital to the US-led coalition's goal of handing responsibility for security to Iraqis, so foreign troops can return home.

In another sign of lawlessness in Basra, gunmen on Monday robbed $740,000 (euro560,946) from a bank about half a mile from the raided police station.

The car bomb in Baghdad, meanwhile, struck a mostly Shiite district to the east that attracts crowds of shoppers and laborers looking for work.

In another part of eastern Baghdad, a suicide bomber exploded in a minibus, killing three people and injuring 19, police said.

Another suicide bomber killed two policemen at a checkpoint at a university entrance in Ramadi, capital of Anbar province, a stronghold of the Sunni-dominated insurgency.

The deaths came a day after Iraq's interior minister said attacks targeting police had killed some 12,000 officers since the 2003 fall of Saddam Hussein.

Christians attended Christmas services in Baghdad and northern Iraq, home to most of Iraq's 800,000 Christians. Some in Baghdad stayed home, however, fearing violence.

Christians are on the fringes of the conflict, which mostly involves Shiite Muslims and Sunni Arabs - but they have been targeted by Islamic militants.

"I hope next year will bring good things and unite all Iraqis because there is no difference between Christians and Muslims," said Abu Fadi, a worshipper who does not use his Christian name because he fears for his safety. "May God bring relief from this."

In another sign of escalating diplomatic tensions between the US and Iran, the White House said Monday that US troops in Iraq detained at least two Iranians and released two others who had diplomatic immunity.

US officials have charged that Iran provides training and other aid to Shiite militias in Iraq - including the equipment used to build roadside bombs. The Tehran regime says it only has political and religious links with Iraqi Shiites.

But Iran is believed to be expanding its shadowy role in Iraq, partly to counter US influence in the region.

In Baghdad, a spokesman for Iraqi President Jalal Talabani confirmed that US troops had detained two Iranians who were in Iraq at his invitation. "The president is unhappy about it," said Hiwa Osman, Talabani's media adviser.

He gave no further details, and the US military said it had no comment.

"We suspect this event validates our claims about Iranian meddling, but we want to finish our investigation of the detained Iranians before characterizing their activities," White House spokesman Alex Conant said Monday. "We will be better able to explain what this means about the larger picture after we finish our investigation."

He said that a routine raid on suspected insurgents netted the Iranians. Two had diplomatic immunity and were released to the Iraqi government, which then released them to Iran, Conant said.