ISLAMABAD, June 7 (Xinhua) -- At least three people, including two policemen, were killed and two others injured when a blast hit a police vehicle in Pakistan's northwestern Khyber Pakhtunkhwa province on Thursday, according to local media and district police.

Local police officials said the vehicle was hit by an improvised explosive device in the Maidan area of Lower Dir district of the province, killing two cops and a passerby on the spot.

local media said a police team was on its way to carry out an investigation of a murder case, which happened last night, when their vehicle was targeted by the miscreants.

Following the incident, security forces and rescue teams rushed to the site and shifted the bodies and injured to a hospital in the district. The two injured cops are said to be in critical condition.

Security forces have condoned off the area and kicked off a search operation to arrest the culprits.

No group or individual has claimed responsibility for the attack yet.?