Pakistani troops killed eight Islamist militants Tuesday in an Afghan border region where insurgents are staging a comeback after a military operation there was declared a success, a local official said.

The fighting came amid continuing reports that the head of the Pakistani Taliban had died as a result of injuries sustained in a U.S. missile strike elsewhere in the northwest in mid-January. On Monday, a Taliban commander said chief Hakimullah Mehsud was alive and promised to provide proof soon.

The clashes in the Bajur region illustrate the tenacity of Islamist militants in northwest Pakistan, most of whom are allied with those waging war against U.S. and NATO troops across the border in Afghanistan.

Bajur was declared free of militants a year ago after a military offensive, but in recent days government officials say security forces have killed dozens of insurgents there. A militant homicide attack there killed 16 people on Saturday.

The latest deaths came during overnight raids in the towns of Damadola and Sewai, local government official Abdul Malik said. He said tribesmen loyal to the government hung the corpses of two alleged militants from an electricity pole in the Inayat Kali area in Bajur, though he did not know when the insurgents were killed.

There was no independent confirmation of the fighting or the identities of the dead.

The Taliban and Al Qaeda are both present in Bajur, the northernmost segment of Pakistan's semiautonomous tribal belt. The tribal regions are a suspected hiding area of Al Qaeda chief Osama bin Laden, and a regular target for missiles fired by U.S. unmanned planes.

The death of militant chief Hakimullah would be an important victory against an Al Qaeda ally already recently driven from its stronghold of South Waziristan by a Pakistani army offensive in October. Hakimullah's predecessor, Baitullah Mehsud, died in a similar attack in August.

The Pakistani Taliban initially denied Baitullah was killed, only admitting his death after Hakimullah was named his heir weeks later.

The U.S. is eager for Islamabad to pursue militants on Pakistani soil, where Washington says they plot assaults on American troops in Afghanistan. Hakimullah Mehsud is believed to have played a key role in a suicide attack on a CIA base in Afghanistan late last year that killed seven agency employees.

Taliban commanders Waliur Rehman and Qari Hussain are seen as the two most likely successors to replace Mehsud. Hussain is known as the group's chief trainer of suicide bombers. Rehman was the commander in South Waziristan.