ISLAMABAD, June 29 (Xinhua) -- Three people were killed and two others injured when unknown militants opened fire on their vehicle in Pakistan's northwest Khyber Pakhtunkhwa province on Saturday night, official sources said.

The incident occurred at about 10:40 p.m. local time (GMT 1740) when a pro-government peace militiaman was traveling in the vehicle along with others, police sources told Xinhua.

No group has claimed responsibility for the attack, but police suspect the involvement of local militants with whom the militiaman had longstanding tensions, the sources added.

The injured were shifted to a nearby hospital.

Following the incident, police rushed to the site and cordoned off the area for investigation. Enditem