Updated

The Pakistani military is confronting tribal leaders in the region where Usama bin Laden (search) may be hiding, apparently using the threat of violence and home destruction to force them to supply information on extremists in the area, the top American general in Afghanistan said Tuesday.

Lt. Gen. David Barno expressed hope that recent efforts by the Pakistani military, combined with a change in U.S. counterinsurgency tactics in Afghanistan, would create a "hammer-and-anvil" effect along the mountainous border between the two countries, in which one force would drive the Al Qaeda (search) fighters into the other.

In Pakistan (search), soldiers and government paramilitaries have been meeting with tribal chiefs for at least six weeks and threatening them with "destruction of homes and things of that nature" unless they cooperate, Barno said.

"That they're confronting the tribal elders and they're holding them accountable for activities in their areas of influence is a major step forward," Barno said, briefing reporters at the Pentagon via teleconference from Afghanistan.

Pakistan says it does not want U.S. forces operating inside its borders, and the U.S. government says it won't go in without Pakistani permission. Since 2002, Pakistan's army has staged several operations targeting Al Qaeda fugitives. Residents have reported seeing a small number of foreign personnel on such operations, but Pakistan denies it.

Al Qaeda supporters, possibly including bin Laden — the Al Qaeda leader — are thought to be in the semiautonomous tribal regions of Pakistan, where many are sympathetic to the Taliban. Previously, the Pakistani military had left the area alone.

The government of Pakistan's president, Pervez Musharraf, has lately been in the hot seat since the acknowledgment that one of its most prominent senior scientists was selling nuclear technology to several other countries. But the Bush administration has also made a point of praising its efforts in the war on terrorism.

On the Afghan side of the border, Barno said U.S. forces are moving away from targeted raids on suspected militants and toward a system of a body of troops having a specific region to patrol and protect.

U.S. military officials have previously said American troops will step up combat operations in Afghanistan with the spring thaw.

Barno said Al Qaeda's presence in strongest in the eastern part of the country, while holdouts from Afghanistan's homegrown Taliban movement are strongest around Kandahar in the south.

He said they are no longer massing forces for combat, instead turning to bombings against soldiers, aid workers, and civilians, in part to get publicity.

"They can disrupt some of these very worthy non-governmental programs of aid across the country by doing this," Barno said. "It's classic terrorism. It's murder and mayhem. And it's sowing terror among those that don't have defenses."

Barno also backed off from earlier statements from his command that bin Laden would certainly be caught within the year.

"There are no certainties in the warfighting business out here," he said.

He also said he does not have information that would suggest extremist fighters from Afghanistan and Pakistan are moving in significant numbers to fight the U.S. occupation in Iraq.

"We're continuing to be watchful in terms of any movement of these [people] back and forth," he said. "But I don't think there's strong indicators that I've been able to see in that regard yet."

Some intelligence suggests that anti-American fighters in both countries are sharing information on their tactics, he said.