The Mangaro outpost in Kurram district came under pre-dawn raid by more than 50 rebels who came from Afghanistan, a security official said.
"The security forces responded the attack with heavy fire, killing 12 attackers and forcing others to retreat back into Afghanistan," a security official said.
Radio Pakistan confirmed the raid and reported that the security forces had launched search operation in the area.
Afghanistan and Pakistan share a 2,250-kilometer border and militants from both sides routinely launch cross-border attacks before fleeing back over the border. Much of the border area is remote.
