At least six people were injured in a suicide blast near a bus carrying employees of Saindak Copper Gold Project in Dalbandin, Chaghai on Saturday.
A suicide bomber attempted to attack the bus but did not succeed.
Commissioner Quetta Division Muhammad Hashim Ghilzai confirmed that a suicide bomber detonated explosives near the bus.
"Three foreigners and three FC personnel were injured in the blast," the commissioner said.
The injured have been shifted to a nearby hospital.
Security forces have sealed off the area and investigations into the incident are under way.
Saindak Copper-Gold Mine is located near Saindak town in Chagai District of Balochistan. The discovery of copper deposits at Saindak was made in the 1970s in collaboration with a Chinese engineering firm.