KANDAHAR, Afghanistan (AP) -- A suicide attacker rammed a car laden with explosives into a vehicle carrying Britons in southern Afghanistan on Sunday, wounding four of them, a U.S.-led coalition commander said.

The attack occurred in Kandahar city, said Col. Steve Bowes, a Canadian commander with the coalition.

The four were traveling in a Landcruiser four-wheel-drive when the suicide bomber in a Toyota Corolla attacked them, Bowes said.

Two of the Britons were in serious conditions, while the other two were lightly wounded, Kandahar Gov. Asadullah Khalid said. He said the four were civilians were working on a customs project in Kandahar, a former stronghold of the Taliban.

The suicide attacker died in the assault, the governor said.

The Britons' vehicle was burned in the attack. Canadian troops based in the city cordoned off the area and rushed the four to hospital.

The bombing was the third suicide attack in Afghanistan in two weeks.

The spate of attacks comes amid a major upsurge in violence across much of the country since March that has left more than 1,300 people dead.