Nine US soldiers have been killed in a suicide bomb attack on a base north of Baghdad, military officials have said.Some 20 troops and an Iraqi civilian were injured in the attack, which happened in the volatile province of Diyala, to the north-east of Baghdad.
There has been fierce fighting in Diyala recently, pitting US and Iraqi forces against Sunni and Shia militias.
It is thought to be the US military’s worst single loss since late 2005, when 10 marines were killed near Falluja.
More than 3,300 US troops have been killed and some 24,300 have been injured in Iraq since the conflict began.
In a brief statement released early on Tuesday, the US military said a suicide car bomber attacked a patrol base near Baqouba, the capital of Diyala province, on Monday.
It is in no-one’s intention that this (the wall) is going to be a permanent state of affairs
Fifteen of the wounded soldiers were later able to return to work, the statement said.
American troops in the province come under frequent mortar and small arms attack, but a frontal assault like this on a base is rare, says the BBC’s Andrew North in Baghdad.
Most are now too well defended for suicide attackers to get close. But the base that was attacked is a smaller installation and so may have been more vulnerable, our correspondent adds.
The latest bombing followed a series of blasts in the town of Ramadi on Monday that killed 20 people and hurt dozens.
Three cars exploded in quick succession near a restaurant and market in Ramadi’s western district of al-Taamim.
Earlier on Monday blasts hit Baqouba and Mosul, and near where the new US envoy was giving his first briefing in Baghdad.
Ambassador Ryan Crocker said the next few months were critical in the effort to reconcile Iraq’s warring communities and urged the government to make use of a US-led security plan in the capital.
He also defended the thinking behind a controversial wall being built around the flashpoint Adhamiya area, a Sunni enclave on the mainly Shia east bank of the Tigris.
On Sunday Iraqi Prime Minister Nouri Maliki said he had ordered a halt to the project after it drew strong criticism from residents and Sunni leaders.
The latest US deaths also came as Democratic Party lawmakers in the US Congress agreed to merge House and Senate versions of a spending bill for Iraq, which include a timeline for the withdrawal of US troops.
The bill calls for a withdrawal to start no later than 1 October 2007, with a non-binding deadline of 31 March for a total pullout. US President George W Bush says he will veto the bill.