MIRAMSHAH, Nov 20: Four security personnel were killed and 12 injured when a suicide bomber rammed an explosives-laden van into a checkpost in Shawa tehsil of North Waziristan on Wednesday.

At the same time, a group of militants stormed into an adjacent building housing security forces.

According to security officials, the bomber attacked the checkpost on Bannu-Mirali road in the morning and killed four Frontier Corps soldiers and injured 12 others.

Sources said that about 60 FC personnel, scouts and Khasadar Force were manning the checkpost.

The powerful explosion damaged hospital and school buildings in the area.

Security personnel cordoned off the area and fired back at the militants, imposed curfew in the area and closed the road to traffic.