Bomb kills soldiers and destroys school

They were the first known US military fatalities in Pakistan's tribal regions near the Afghan border, and a major victory for militants who have been hit hard by a surge of US missile strikes and a Pakistani army offensive.

The blast also killed three schoolgirls and a Pakistani soldier who was travelling with the Americans. Two more US soldiers were wounded, along with more than 70 other people, mostly students, officials said.

The attack took place in Lower Dir, which like much of the north-west is home to pockets of militants. The Pakistani army launched a major operation in Lower Dir and the nearby Swat Valley last year that succeeded in pushing the insurgents out, but isolated attacks have continued.

The US soldiers were travelling with Pakistani security officers in a five-car convoy that was hit by a roadside bomb close to the Koto Girls' High School. The blast flattened much of the school.

"What was the fault of these innocent students?" said Mohammed Dawood, a resident who helped the injured.

The soldiers were in the region as part of a US mission to train members of the paramilitary Frontier Corps, Pakistan's army and the US Embassy said.

They were driving to the opening of a girls' school renovated with US humanitarian assistance. The school that was badly damaged in the blast was not the one where the convoy was heading, security officials said.

The blast was detonated by remote control, but it was not clear whether the attackers knew the convoy was carrying soldiers.

The attack highlights the presence of US troops on Pakistani soil at a time when anti-American sentiment is running high.

In a statement, the US Embassy said three American military personnel were killed and two were injured in the attack.