PESHAWAR, Pakistan (AP) — A suicide bomber’s explosive vest went off in the house of a pro-government tribal elder in the northwestern Pakistani city of Peshawar on Monday, killing four women, police said.

It was not clear if the attacker set the vest off deliberately. He had run into the home of the elder, Jan Mohammad Afridi, in the city’s Chamkani area, after local residents found him suspicious and the police started chasing him, said police chief Ahsan Shah.