Islamabad, March 30 : Four policemen were killed and six others injured in two coordinated attacks on Thursday in Pakistan's Khyber Pakhtunkhwa province, an official said. Some unknown attackers stormed a checkpost with sophisticated weapons in Lakki Marwat district, injuring five cops in an exchange of fire, Xinhua news agency quoted the police official as saying. The attackers fled the scene amid retaliatory fire by the police who also called for an extra contingent of force for a search operation. A police officer with his three gunmen and a driver left for the site, after receiving information regarding the incident and was attacked on the way. "The deputy superintendent of police Iqbal Mohmand's vehicle was attacked by a roadside planted bomb when he was on the way to the check post," the spokesperson added. The attack killed the officer and his three gunmen whereas his driver got critically injured. All the injured were shifted to a nearby hospital. No group has claimed the attack yet. /IANS