BAGHDAD — The US military yesterday accused Iran for the first time of a direct role in an attack killing American troops in Iraq, saying it helped direct a sophisticated militant raid in January in which five soldiers died. The claims portrayed Tehran as waging a proxy war in Iraq through Shiite extremists.The claims escalated US accusations that Iran has been arming and financing Iraqi militants, and for the first time linked the Iranian effort to its ally, Lebanon’s Shiite Hizbollah militia. The allegations were likely to fuel US-Iranian tensions and could endanger Iraqi government efforts to hold a new round of talks between the two countries.

US military spokesman Brig. Gen. Kevin J. Bergner said the Quds Force, part of Iran’s elite Republican Guards, was seeking to build an Iraqi version of Lebanon’s Hizbollah to fight US and Iraqi forces — and had brought in Hizbollah operatives to help train and organise militants.

“Our intelligence reveals that the senior leadership in Iran is aware of this activity,” Bergner told a Baghdad news conference. He said it would be “hard to imagine” that Iran’s supreme leader Ayatollah Ali Khamenei did not know about the activity.

Iran has denied past claims that it was backing Iraqi militants — including accusations that it was providing them with a deadly form of roadside bomb — the explosively formed penetrator. Its ally Hizbollah has denied having any role in Iraq, saying it operates only in Lebanon.

Iranian Foreign Ministry spokesman Mohammad Ali Hosseini rejected the allegations yesterday, saying “American leaders have gotten into the habit of issuing ridiculous and false statements without providing evidence, with political and psychological aims.”

Bergner said interrogations of an alleged Lebanese Hizbollah operative, Ali Mussa Dakdouk, and an Iraqi militant Qais al-Khazaali — both captured in March in the southern city of Basra — and documents seized with them showed an extensive Quds Force programme.

The Iranian force is providing up to $3 million a month to Iraqi militants and bringing them to three training camps outside Tehran to learn how to carry out bombings, raids and kidnappings, Bergner said.

Dakdouk, a 24-year veteran of Hizbollah, was sent to Iraq “as a surrogate for the Iranian Quds Force” to finance and arm militant cells known as “special groups,” the general said.

The goal was to organise militants “in ways that mirrored how Hizbollah was organised in Lebanon.” Hizbollah is one of the region’s most disciplined and powerful militant groups, able to fight Israel’s military to a near standstill in a war last summer.

Dakdouk told his interrogators that the militants behind the January 20 surprise attack in the southern city of Karbala “could not have conducted this complex operation without the support and direction of the Quds Force,” Bergner said.

The Karbala attack was one of the most sophisticated against US forces in the four-year-old Iraqi war.

Up to a dozen fighters were disguised as an American security team with false IDs, enabling them to get past checkpoints to reach a provincial government building in Karbala, where they opened fire with machine guns and explosives. One US soldier was killed in the initial attack, and four others were abducted and found shot to death soon after.

Al-Khazaali was in charge of special groups around Iraq and confessed to ordering the Karbala attack, Bergner said. A 22-page document seized with him detailed the operation, showing that the Quds Force had developed detailed information on US soldiers’ “shift changes and defences” at the government building, “and this information was shared with the attackers,” Bergner said.

The Shiite-led Iraqi government of Prime Minister Nouri al-Maliki is backed by the US but is also closely tied to Iran, and it has hoped that talks between the two rivals could ease the tensions between them and reduce Iraq’s violence.

An initial Baghdad session in February between ambassadors from the two countries, however, made little progress, overshadowed by accusations by each side that the other was fuelling Iraq’s turmoil. Iraq is trying to organise a second meeting, but no date has been set.

Sami al-Askari, al-Maliki adviser, said, “We don’t rule out that there is Iranian interference by financing armed groups, whether Shiite or Sunni, or even that there might be some Hizbollah elements training the groups.”

But he insisted the US accusations “will not affect the Iranian-American meeting.”

In Washington, State Department spokesman Sean McCormack echoed Bergner’s charges, saying they were “another data point in what is a troubling picture of Iranian negative involvement in Iraq.”

An American soldier was killed yesterday by an explosion in Salahuddin province, a centre for Sunni insurgents northwst of Baghdad. The US military also reported the deaths of five US service members killed in fighting a day earlier, in attacks in Baghdad and western Anbar province. The deaths brought to 3,583 the number of members of the US military who have died since the beginning of the Iraq war in March 2003.