PESHAWAR: Gunmen on motorcycles shot dead two police officers Saturday in northwest Pakistan, while security forces killed four militants in fighting elsewhere in the region, officials said.

The policemen were killed in Hayyatabad, on the outskirts of the northwestern city of Peshawar, area police chief Mir Afzal Khan said. The assailants fled to the nearby Khyber tribal region after the attack, he said.

Police were investigating a possible motive for the shooting.

Overnight, a gunbattle between militants and security forces broke out in the northwestern town of Mohmand, near the Afghan border, a security and an intelligence official said Saturday. Four militants were killed in the fighting and another three were wounded.

The officials said the troops retaliated after insurgents attacked a security checkpoint in the Sagi village area.

The officials spoke on condition of anonymity because they were not authorized to brief the media.

Pakistan has carried out operations against Taliban militants in Mohmand, but violence persists in the region and other parts of the tribal belt in the country's northwest.