Five people, including three police, were killed and several others wounded outside a religious centre in the Himalayan tourist town of Mingora by the bomb, local administration chief Syed Mohammed Javed told AFP by telephone.

The policemen were clearing traffic at Mingora town 130 kilometres (80 miles) northwest of Islamabad, when a bomb exploded in a white car, Javed said, adding that it was unclear whether the car's occupant died.

Mingora is in Swat district, a stronghold of Tehrik Nifaz-e-Shariat-e-Mohammadi, a banned extremist group with close ties to the clerics of Islamabad's Red Mosque.