Gunmen on Tuesday killed the driver of a NATO supply truck in northwest Pakistan on the Afghan border, officials said.

The shooting took place in the Jamrud area of Khyber, one of seven districts in Pakistan's semi-autonomous tribal belt where Taliban and Islamist militants are active.

"Two gunmen on a motorcycle fired at a NATO truck and killed its driver when a convoy of three trucks was passing," local government official Asmatullah Wazir told AFP.

He said an assistant of the driver was wounded and that the gunmen escaped.

Imran Ahmed, a doctor at the local hospital, said the driver was shot in the head, and that his assistant was shot twice on the shoulders.

"We have received the dead body of the driver. He was hit in the head. The helper was hit by two bullets on shoulders," he said.

Wazir said the authorities conducted a search operation in the area after the attack and arrested 19 suspects.

Khyber's top administration official, Mutahir Zeb, confirmed the attack on the NATO truck and the driver's death, saying there had been no immediate claim of responsibility.

Islamabad reopened the Afghan border to NATO traffic in August, ending a seven-month blockade imposed after botched US air raids killed 24 Pakistani troops in November 2011.

Pakistan and the United States signed a deal allowing NATO convoys to travel into Afghanistan until the end of 2015.