The terrorists carried out the attack on unarmed Traffic Police forces who were on patrol on a road between the cities of Khash and Taftan on Sunday.
The assailants, waiting in ambush, sprayed bullets at the sedan of the Traffic Police on the desert road.
The provincial Police command has vowed revenge for the terrorist attack.
Located in the southeast of Iran, Sistan and Balouchestan borders Pakistan and Afghanistan and has a long coastline by the Sea of Oman.