The incident took place near Pishin Bypass in Balochistan.
According to sources, the bomb targeted the Assistant Commissioner of Barshore’s car. The AC was not in the vehicle at the time of the attack.
Security officials have cordoned off the blast site and launched search operation in the area to nab the suspects.
Earlier on July 14, a suicide blast ripped through a crowd at a political rally in the town of Mastung, near the Balochistan provincial capital Quetta, killing 128 people and wounding 150.
Among the dead was Siraj Raisani, who was running for a provincial seat with the newly-formed local Balochistan Awami Party (BAP).
The attack was the most lethal since Tehreek-e-Taliban militants assaulted the Army Public School in the northwestern city of Peshawar in 2014, killing over 150 people, mostly children, and one of the deadliest in Pakistan s long struggle with militancy.