ISLAMABAD - Pakistani troops killed eight insurgents Saturday in gunbattles in the Swat Valley, the military said, underscoring that the Taliban threat in the region persists more than three months after a government offensive to expel the militants.

The Taliban had ruled the valley for months, enforcing a harsh interpretation of Islam. The army claimed to have killed more than 1,800 militants in the operation over the summer that displaced around 2 million people. The top Taliban leadership in the valley fled the offensive and remain at large.

Most of the displaced people have returned home, but the continuing violence shows the Taliban have not been eliminated from the region.

"We fought gunbattles with the militants and killed eight of them in a search operation," army spokesman Maj. Mushtaq Ahmad told The Associated Press. The incident took place in Charbagh town, he said.

Five bodies were found in neighboring Malakand district, local police official Mohammad Kamal said. He added that authorities were investigating to ascertain their identity, though they appeared to be militants.

After concluding the campaign in the valley, the army launched an operation in mid-October in the Taliban stronghold of South Waziristan, a tribal region along the Afghan border. The army lately has been fighting street battles with the militants in key Taliban bases in the region, where it claims to have killed hundreds of insurgents.

The militants have responded by carrying out attacks in Pakistani cities, killing more than 300 civilians and security personnel.

A truck bombing Friday targeted the regional headquarters of the country's top intelligence agency in the northwestern city of Peshawar, killing seven officials of the Inter Services Intelligence and three civilians.