Obama's Kabul trip blasted

Suicide attackers launched a dawn attack on the outskirts of Kabul, killing seven, just hours after US president Barack Obama visited the Afghan capital and claimed that the last three years of fighting had broken the Taliban's momentum.

Witnesses said at least four attackers were involved, shrouded in all-enveloping burqas. They headed to the Green Village compound, which houses hundreds of foreign workers including UN staff, EU police trainers and many private security contractors.

A car bomb blasted away the gate and part of the nearby wall, killing at least one student from the nearby Kabul boys high school and a Nepali compound security guard, the Capital's police chief General Ayoub Salangi said.

Wreckage: Afghan firefighters douse a burning vehicle in Kabul after a suicide bomb attack. Taliban insurgents claimed a suicide attack in Kabul, shortly after US President Barack Obama left the city after an overnight visit. pic/afp

Four civilians in a passing car were also killed almost immediately, said an intelligence official. The blast was loud enough that it was heard on the other side of the city, and left a large crater in the road.

"I was walking to school when I saw a very big explosion. A car exploded and flames went very high into the air," said student Mohammad Wali.

"Then I saw a body of one of my classmates lying on the street. I knew it was a suicide attack and ran away. I was so afraid."

Several other students and teachers were among the injured, said the interior ministry, which put the death toll at seven, excluding the insurgents.

The Taliban claimed the attack was a response to Obama's presence in Afghanistan.

"When we heard about Obama's visit we quickly planned the attack," said spokesman Zabihullah Mujaheed.

"This is a message for Obama and other foreigners who are trying to fight against the mujahideen that they will not be able to resist," he added.

In the brief speech Obama focused on the handover of responsibility for military operations from American and other troops to domestic Afghan forces.

That message aims to reassure both those Americans who are keen to see a quick end to an increasingly unpopular war, and those in Afghanistan and elsewhere who fear too hasty a departure could pave the way for civil war or the Taliban's return to power by force.

He said the shift would ensure US military involvement in the country would end by 2014 apart from small training and counter-terrorism issues.

"We will not build permanent bases in this country, nor will we be patrolling in cities and mountains. That will be the job of the Afghan people," he said.

Obama made only a short reference to the killing of Osama bin Laden but his speech focused more on al-Qaeda than the Taliban.