Islamabad, Pakistan (CNN) -- Unidentified gunmen on motorbikes opened fire and killed the driver of a supply truck for NATO troops in southwest Pakistan on Sunday, a senior government official told CNN.
Noorul Haq Baloch, an official of Pakistan's southwestern district of Mastung in Balochistan province, said the incident happened in the area of Khad Kocha, 50 kilometers (31 miles) south of Quetta.
Baloch said the truck was going to Afghanistan from the southern city of Karachi.
The gunmen escaped after killing the driver, he said.
"The gunmen fired multiple bullets (that) killed the driver and damaged the container," Baloch said.
Supplies for NATO in Afghanistan are transported from Pakistan through private contractors.
Dozens of oil tankers and containers pass through Pakistan daily to supply fuel and other supplies to NATO troops battling insurgents in Afghanistan.
Some of them are attacked by militants on their way to Afghanistan.
In Balochistan province in October, dozens of oil tankers destined for Afghanistan caught on fire after being attacked by gunmen.