Islamabad, Aug 2 : At least two policemen were killed and two others wounded in an attack on a judges' convoy in Pakistan's northwestern Khyber Pakhtunkhwa province on Friday, police said.

The attack happened near the Bhagwal area of Tank district of the province when unknown "terrorists" targeted the judges' vehicle with gunfire, critically injuring four cops, said police officials in Tank district, Xinhua news agency reported.

Two of the injured policemen succumbed to their injuries at a hospital in the district, said police officials, adding that the judges remained unhurt, who were on their way home under tight security arrangements.

A heavy contingent of police reached the area after the attack. Police have started an investigation and launched a search operation in the surrounding areas to arrest the perpetrators involved.

No group has so far claimed responsibility for the attack.

/IANS