A bomb blast at a religious seminary in the Pakistani city of Peshawar today killed at least seven people and wounded more than 80, police and hospital officials said.

There was no immediate claim of responsibility for the bomb in the northwestern city, near the border with Afghanistan, which has long been plagued by Islamist violence.

“Unknown people planted explosives in a plastic bag,” said a police officer who declined to be identified as he is not authorised to speak...