It's a rough job, but $25 million isn't a bad salary.

This is the attitude the military hopes Afghans will take toward the difficult and dangerous task of searching through caves for Usama bin Laden and other Al Qaeda leaders, Defense Secretary Donald H. Rumsfeld said Monday.

The bounty offered for bin Laden and his top aides, plus additional reward money from the CIA, should encourage "a large number of people to begin crawling through those tunnels and caves, looking for the bad folks," Rumsfeld said.

He also said the United States would not allow Taliban leader Mullah Mohammed Omar to leave his hometown of Kandahar, even if the anti-Taliban forces surrounding the city offer him safe passage. Rumsfeld added that he hoped Taliban and Al Qaeda fighters holding the northern Afghan town of Kunduz are killed or captured, not released.

"The idea of their getting out of the country and going off to make their mischief somewhere else is not a happy prospect," he said. "So my hope is that they will either be killed or taken prisoner."

Speaking on the 44th day of U.S. bombing in Afghanistan, President Bush said the military was closing in on bin Laden, the chief suspect in the Sept. 11 terrorist attacks. "The noose is beginning to narrow," Bush said.

"If our military knew where Mr. bin Laden was, he would be brought to justice," Bush said following a Cabinet meeting. Asked whether he had evidence that U.S. forces were closing in on bin Laden, Bush said, "It's going to be hard to tell you that without compromising the search, except I can point to the map of Afghanistan, where more and more territory are now in friendly hands."

Rumsfeld was more cautious.

"As enemy leaders become fewer and fewer, that does not necessarily mean that the task will become easier," he said. "People can hide in caves for long periods. This will take time."

He denied reports that U.S. intelligence has defined a narrow search area for bin Laden and his associates.

"To try and think that we have them contained in some sort of a small area I think would be a misunderstanding of the difficulty of the task," he said.

If the job of finding bin Laden falls to the U.S. military, it will require different kinds of troops than the special operations forces now in Afghanistan, Rumsfeld said. He did not elaborate, but other officials have said an infantry unit like the Army's 10th Mountain Division might get the assignment.

Rumsfeld said the special forces in Afghanistan — now numbering several hundred — had not yet pursued any Taliban or Al Qaeda leaders into neighboring Pakistan. "If one of those folk that we particularly wanted was known" to be crossing a border, "we might have an early intensive consultation with the neighbors," he added.

To spread word of the $25 million reward for getting bin Laden and a "select few" of his lieutenants, the U.S. military is dropping local-language leaflets over Afghanistan "like snowflakes in December in Chicago," Rumsfeld said.

Intelligence officials believe bin Laden is in a rural area of the country, not under northern alliance control — meaning either southeast of Kandahar or around cities like Jalalabad in the east or Kunduz in the north.

In the past, bin Laden has traveled with at least a small, armed security force, and he's believed to now use people as couriers, because he knows the United States can eavesdrop on his phone conversations.

Although bin laden might try to flee Afghanistan, many believe he is more likely to go underground. During the war against the Soviet Union in the 1980s, he spent millions from his personal fortune to create a network of underground hide-outs and fortified bunkers out of an ancient network of water trenches.

Rumsfeld said he would travel to Fort Bragg, N.C., home of the Army Special Operations Command, on Wednesday to receive a briefing on special operations and talk with troops.

The Associated Press contributed to this report.