ISLAMABAD - Pakistani troops and militants battled near the edge of the top Taliban commander's stronghold yesterday as violence in the country's volatile northwest spread and intensified, with multiple battles killing scores of insurgents.

The clashes near the border with Afghanistan were sparked by militant attacks, however, and there was no sign that the military was launching a major offensive in the lawless tribal belt where the Taliban and al Qaeda have entrenched themselves in recent years.

Officials in Washington say privately that they would like the Pakistani army to extend its ongoing operation to oust the Taliban from the northwestern Swat Valley region into North and South Waziristan. Both areas are hotbeds of militant activity that al Qaeda and the Taliban are accused of using as bases to foment violence against American troops in Afghanistan.

Pakistan has not announced plans for a new offensive in the tribal belt, and may first want to finish the Swat operation and deal with the huge humanitarian crisis it spawned. More than 2 million people have been uprooted from their homes by the fighting.

But fighting has spilled out of Swat in the past week, as militants stepped up attacks on security forces in retaliation for the offensive, and the army has replied with artillery, gunships and assault forces in some areas.

The army said in a statement that about 400 militants using guns and rockets attacked two forts at Siplatoi and Jandola, in South Waziristan, a rugged, remote region along the Afghan border where Pakistani Taliban chief Baitullah Mehsud is based. They were repelled in battles that killed 22 militants and wounded "a large number" of others, as well as leaving three troops dead, it said.

They were the largest skirmishes in South Waziristan since the Swat offensive began, though the area has been hit by smaller attacks.

In another area of the northwest, the military said that it had secured two villages in Upper Dir where militants had holed up after being fought into retreat during five days of clashes with a citizens' militia that sprang up to deliver payback for a recent deadly mosque bombing. It said that 34 militants were killed, and one civilian died in a militant rocket attack.

The army used helicopter gunships to target militant positions in the operation, which also included the Bannu and Hangu regions as well as Upper Dir, and two local Taliban commanders were among the dead, said three intelligence officials. They spoke on condition of anonymity because they were not authorized to give information to reporters.

Taliban in the villages of Shatkas and Ghazi Gay were still beseiged by the militia, which destroyed a number of bunkers and an ammunition cache, the military said.

The government has exhorted Pakistanis to rise up against militants in their areas, trying to capitalize on a recent shift in public mood against the Taliban, which for years have been met with ambivalence or tacit support in many areas, especially the religiously conservative northwest.

Clashes also continued in several areas in Swat, killing 10 militants, the army said. The military said that it has killed more than 1,300 militants during the offensive and reclaimed most of the region. *