At least three people were killed and dozens were wounded in a suicide attack on Pakistani security forces in the Jamrud area of the nation's Khyber Agency on Tuesday.
The attack targeted a paramilitary vehicle.
The vehicle belonged to the Khasadar, or tribal police force.
At least 43 wounded persons have been rushed to a hospital in Peshawar, about 20 km to the east.
All hospitals in the area have alerted to expect more wounded from the site of the blast.