Iraqi insurgents, using a suicide bomber to explode a fuel tanker, launched one of their biggest assaults in months on a joint US and Iraqi outpost today, killing two US soldiers and wounding 17 others.
The attack, north of Baghdad, was part of a day of bombings and shootings by militants as tens of thousands of US and Iraqi forces fanned out in the capital in a new operation to crack down on rampant sectarian violence.
Three US soldiers were killed and two others wounded in a roadside bomb blast southwest of Baghdad, the US military said.
More than 40 Iraqis were killed, including 10 in bombings in Baghdad, in other attacks.
Near Falluja in the west, 13 members of a single family were shot dead by suspected al-Qaeda militants while in nearby Ramadi two suicide bombers killed 11 people in an attack on the home of a tribal leader who had opposed al-Qaeda.
Iraqi police said a suicide bomber at the wheel of a fuel tanker blew himself up as US forces entered an Iraqi police station in the town of Tarmiya, which US troops use as an outpost. The self-styled Islamic State in Iraq, an al-Qaeda-linked group, claimed responsibility for the attack via a Web statement.
The town is a Sunni Arab insurgent stronghold some 40 km (25 miles) north of Baghdad in the notoriously violent province of Salahaddin.
US military helicopters hovered over the area transporting the wounded after the blast, which almost demolished the police station. A US military spokesman in Baghdad declined to provide more specific information on the attack, a rare coordinated assault on a US base.
"It was not just a spontaneous attack. It wasn't just people taking potshots at us," Major Steven Lamb said.
A US military statement said US soldiers secured the area and evacuated the wounded. It was not known if any insurgents were killed.
More than 3,100 US soldiers have been killed in Iraq since the US-led invasion in 2003.
The violence by militants came a day after two bombs killed 60 people in a Shia market area in Baghdad in the bloodiest assault since the new crackdown by US and Iraqi forces began on Wednesday.
US military officials have warned that militants could strike in areas outside Baghdad while US and Iraqi forces focus their efforts inside the capital to end sectarian violence that authorities fear could lead to all-out civil war.
The bombings in the capital that killed 10 people underscored the challenge of stabilising the city that is the epicentre of Iraq's bloodletting.