Clashes are common in the area, but the death toll from the fighting Monday was unusually high on the Pakistani side.

The raid took place in Akka Khel village in the Khyber tribal area, said Farooq Khan, an official.

Pakistan army spokesman Maj. Gen. Athar Abbas confirmed the number of soldiers killed and said they were from the paramilitary Frontier Corps, which is mainly used to fight in the northwest.

Another military official said helicopter gunships were called in to support the troops after the fighting escalated.

It was unclear which militant group was targeted in the raid, but the Pakistani Taleban have frequently clashed with security forces in Khyber. The group has declared war on the Pakistani government, partly because of its alliance with the US

The Pakistani Taleban have also targeted trucks carrying supplies through Khyber on their way to NATO troops in Afghanistan.