Police said two men on a motorcycle had opened fire on the FC checkpost on Saryab road in which two havaldars were killed.
"In the return firing from the FC personnel, one of the attackers was killed while the other one was captured alive in a injured condition," one official said.
He said one FC personnel was also injured in the firing.
The FC personnel killed in the attack included Havaldar Akbar and Sepoy Ali.