A bomb exploded outside a Pakistan court building on Thursday, killing five people and wounding more than 10 in the northwestern city of Peshawar, police said.

"Five people, including a policeman, died and more than 10 people were injured in the bomb blast," police official Mohammad Karim Khan told AFP.

"A van carrying prisoners was just passing at the same time of the explosion at the main gate of the judicial complex," he added.