Pakistani truck drivers wait to begin their trip for Nato troops. – AP (File Photo)

QUETTA: Gunmen killed a Nato supply truck driver on Friday after opening fire on a convoy heading to Afghanistan from Pakistan's troubled southwest, officials said.

An unknown number of attackers on motorcycles signalled for the convoy to stop and opened fire after drivers ignored them, before the gunmen fled the scene, local official Mohammad Azam told AFP.

The incident took place in Baghbana town of Khuzdar district, 250 kilometres south of Quetta, the main city of Balochistan province, Azam said.

“A driver of one Nato supply truck was killed, all other drivers and their helpers remained safe,” he said by telephone.

Nato supply trucks and oil tankers are targets of frequent attacks blamed on insurgents attempting to disrupt supplies for more than 130,000 international troops fighting in Afghanistan.

Most supplies and equipment required by coalition troops in Afghanistan are shipped through neighbouring Pakistan, although US troops increasingly use alternative routes through Central Asia.