Pentagon officials believe Usama bin Laden may be cornered with a number of foreign Al Qaeda fighters under attack by Afghan tribal forces and U.S. special forces commandos in a rugged canyon in Afghanistan, a senior defense official said Thursday.
Fiercely resisting Al Qaeda troops — bin Laden possibly among them — are corralled in the Agam valley and the Wazir valley, two parallel canyons between high mountain peaks. Afghan opposition forces are blocking the north ends of both north-south valleys and advancing on the Al Qaeda forces.
Intense bombing and advances by U.S. commandos and anti-Taliban rebels have reduced substantially the area in which bin Laden and his forces can operate safely within the cave-dotted mountains near Tora Bora, U.S. officials said, speaking on the condition of anonymity.
U.S. officials also said they had sent more special operations forces into the Tora Bora region, where they may engage in direct combat with Al Qaeda fighters who could be protecting bin Laden.
While the officials believe bin Laden may be bottled up with his forces, they admit he could be elsewhere in Afghanistan. Earlier, tribal commanders said they thought the terrorist leader had escaped toward the Pakistan frontier.
Heavy snow fell around the Tora Bora area in Afghanistan's eastern White Mountains, making escape more difficult for the Arab and foreign Muslim fighters trapped for days in the heavily forested canyon after fleeing Al Qaeda caves.
U.S. warplanes provided close air support as anti-Taliban fighters with the eastern alliance — with American special forces moving alongside to call in U.S. airstrikes — staged a massive assault launched after a second deadline for the Al Qaeda fighters to surrender passed at noon Thursday.
After sundown Thursday, B-52 bombers carpet-bombed the higher mountain ridges near the Pakistan border, creating spectacular orange flashes in the night. An AC-130 gunship resumed attacks for the third night in a row.
If not for the surrender talks over the past two days, "this would have been finished," Hazrat Ali, security chief for the eastern alliance, said. "Now we will fight them until we annihilate them."
In Washington, Defense Secretary Donald H. Rumsfeld said the Pentagon believes bin Laden is still in Afghanistan, though he acknowledged there were reports he had left the country.
He said the United States was getting "scraps of information" about bin Laden from Afghans, Pakistanis and others. "He is in hiding. We are asking everyone to help."
As for bin Laden's fighters, Rumsfeld said, "There's no doubt in my mind that any number of Al Qaeda have gone across various borders and do intend to fight another day and we intend to find them and keep looking."
In part to convince any doubters — particularly in the Middle East — that bin Laden was behind the Sept. 11 terror attacks in the United States, the Pentagon on Thursday released a videotape of the Al Qaeda leader explaining the planning of the suicide hijackings.
Ali, of the eastern alliance, said he was not sure if bin Laden was trapped with his men in Tora Bora or even in the area at all.
The Pentagon has said Tora Bora — a network of caves and tunnels in the White Mountains — is the last effective Al Qaeda stronghold in Afghanistan.
Ali said surrender offers by the Al Qaeda fighters holed up in Tora Bora had been "a trick" to give senior leaders a chance to escape.
He said he thought about 700 Al Qaeda fighters, along with at least some of the leaders, remained in the Tora Bora area.
Pakistan has said it has reinforced the border, just a few miles south of the fighting, with helicopters and thousands of soldiers to prevent escape by Al Qaeda figures.
Fiery explosions echoed down the Milawa valley, mixed with heavy machine gun and tank fire. Before dawn Thursday, U.S. planes dropped at least one 15,000-pound "daisy cutter" — and perhaps as many as three. An Associated Press reporter saw a huge, bright magenta fireball that hung in the air and lighted the sky around 3 a.m.
Eastern alliance fighters on the front lines said at least 60 U.S. special forces troops were with them, calling in airstrikes and advising alliance commanders. There were also reports of British special forces operating in the area.
Haji Zahir, who along with Ali and Mohammed Zaman are leading the ground forces against Al Qaeda, said his men made significant progress Thursday afternoon.
"We have advanced a lot, we have captured a lot of positions today," Zahir said. "Today was a difficult day and tomorrow will be, too."
The Associated Press contributed to this report.