A bomb exploded on a bus in Pakistan’s northwestern city of Peshawar on Saturday, killing at least nine people and wounding seven others, AFP reported.

A bomb exploded on a bus in Pakistan's northwestern city of Peshawar on Saturday, killing at least nine people and wounding seven others, AFP reported.

"At least nine passengers have been killed and seven injured. Bomb disposal officials told me that it was a timed device," AFP quoted senior police official, Fazal Wahid, as saying.

Shafi Ullah Khan, another police official, confirmed the attack which occurred as the bus was passing through the city's Matani suburb.

There was no immediate claim of responsibility for the blast, which came hours after militants blew up the election office of an independent candidate in the same region, adding to security fears ahead of historic national polls next month.