Troops backed by artillery and helicopter gunships pounded militant positions in northwest Pakistan, killing at least 60 fighters and injuring many others, the military said Saturday.

The assault happened Friday evening in the Swat valley, shortly after troops found one of two Chinese engineers who had been held hostage by Taliban militants, an army statement said. It said the second Chinese engineer was still in the custody of militants and efforts were under way to rescue him.

"At least 60 Taliban died and many others were wounded during yesterday's operation around the Matta town. This is the same area from where one Chinese engineer was recovered," the statement said.

It was not immediately possible to independently confirm the casualties. Reporters cannot visit the area due to poor security and government restrictions. No Taliban spokesman was available for comment.

The statement did not mention any losses among government forces.

Swat was once a popular tourist destination but the region has become a battle ground since last year when Pakistan sent troops to confront Mullah Fazlullah, a hardline cleric who had launched a violent campaign to enforce Taliban-style Islamic law.

Although the government has regained control in parts of Swat, Fazlullah's men — allegedly reinforced by other militant groups including Al Qaeda affiliates — are still resisting.

Fighting is also raging in the nearby region of Bajur, a militant stronghold overlooking the border with Afghanistan.

The two Chinese telecommunications engineers disappeared in the Dir region of northwestern Pakistan on Aug. 29, and later a spokesman for Taliban militants in Swat had claimed that they were holding the pair.

Beijing has urged Pakistan to rescue the hostages, who reportedly worked for Zhongxing Telecommunication Equipment and were servicing equipment installed in the area.

Pakistani officials have said that the men disregarded advice to take a heavy security detail before traveling to Dir, which lies between Swat and Bajur.