The incident occurred at Tump, a border town in Turbat district, officials of the Levies militia said.
"Unidentified armed men riding motorcycles opened fire from three sides on a car in which four persons were travelling," a Levies official told the media.
The armed men later set the car on fire.
All four persons in the car were burnt to death. The attackers escaped before security personnel reached the spot.
Two of the dead were later identified while two bodies were charred beyond identification.
The cause of the killings could not immediately be ascertained.
No group has claimed responsibility for the attack.
Islamabad: Four persons were shot and burnt to death in the restive Balochistan province of southwest Pakistan on Saturday, security officials said.
First Published: Saturday, March 02, 2013, 13:44