India, Aug. 1 -- Two policemen, including a senior officer, were killed on Friday when unidentified armed men opened fire on a police vehicle in northwest Pakistan, an official said.

The incident occurred in Dera Ismail Khan district in the restive Khyber Pakhtunkhwa province.

No group or individual immediately claimed responsibility for the attack.

According to a Counter Terrorism Department (CTD) official, unidentified armed assailants opened fire on the police van near Shah Alam Mor in Daraban tehsil of the district.

During the attack, two policemen, including an Assistant Sub Inspector, were killed, the CTD official said, adding that the retaliatory fire from the police personnel forced the attackers to flee the scene.

Khyber Pak...