At least nine people were injured in a hand grenade blast at a police station in Pakistan’s southern Sindh province today.

According to the police, a hand grenade went off on its own, reportedly due to heat in a storeroom of the police station, injuring seven policemen. Following the explosion, rescue teams and bomb disposal squad reached the scene and shifted the injured people to a nearby hospital. Police said that an investigation into the incident is still underway to ascertain the exact cause of the blast.