At least four police officers, including an Assistant Sub Inspector, were killed in Khyber-Pakhtunkhwa's Lakki Marwat on Wednesday when unidentified people opened fire on a police van, reported Aaj News.

According to police sources, the victims were ASI Yaqoob Khan, Constable Mustaqeem, Constable Inam and driver Raheemullah.

The Saddar police station van was on usual patrolling when it came under attack, while the culprits instantly ran away from the crime scene.

The investigation into the incident is underway.