The convoy of Deputy Commissioner of Kharan district, Kharan Raziq Dilawary, was attacked in Rachil area.
A security official said that two personnel of Levies force guarding the DC were killed and another two injured in the attack. The deputy commissioner was unhurt.
"The forces fought back and killed one attacker and arrested another alive," he said.
More security forces were sent to the area and a hunt was launched for the attackers.
No one claimed responsibility for the attack but Baloch separatist rebels are active in the area and often target the security forces.