One policeman was killed and two others were injured when suicide bombers targeted a police mobile in Pakistan's northwest Mardan city on Saturday morning, local media reported. Express TV said that two suicide bombers hurled a hand grenade on a police mobile and upon being chased by the policemen, one of them blew himself up and the other escaped to a nearby area. The police conducted a search operation in the area following the blast and killed the on the run suicide bomber. The hand grenade attack injured three policemen who were shifted to a nearby hospital where one of them succumbed to injuries, said the report. The incident happened in Katlang bazaar area of Mardan, a main town in the country's northwest Khyber Pakhtunkhwa province. No group claimed responsibility for the attack yet.