WASHINGTON (Reuters) - Osama bin Laden, whom the United States accuses of masterminding the Sept. 11 attacks, could be in the vicinity of the Agam Valley in eastern Afghanistan where fierce fighting is raging against his followers, a senior U.S. defense official said on Thursday.
U.S. officials believe that bin Laden is in the Tora Bora region near Jalalabad which the U.S. military has been pounding with airstrikes, even unleashing its powerful 15,000-pound ''daisy cutter'' bomb on the area earlier this week.
Additional U.S. special forces numbering in the ``few dozens'' were sent into the Tora Bora region to help the Afghans fighting against al Qaeda forces believed holed up in caves and tunnels in that region, the defense official said.
The reason the United States believes bin Laden is in that area is because of the fierce resistance in the Agam Valley, reports from opposition fighters that he was sighted and other intelligence information that the Saudi-born militant was in the vicinity, the defense official told Reuters.
U.S. forces have been supporting the fighters of local military chief Hazrat Ali that have been battling for several days in that valley, he said. ``It's just very fierce resistance and they're fighting for every foot of ground,'' the defense official said.
``Collectively we think we've got the right area, but I can't narrow it down to a particular cave or a particular grid coordinate,'' the official said on condition of anonymity. ``It is our current thinking that he is in that general vicinity.''
The U.S.-supported fight against al Qaeda forces appears to have locked up pieces of the stretch that includes the Agam Valley connected by a mountain spine to the Wazir Valley, which runs north and south and into Pakistan, the defense official said.
``We are pretty confident that we have the various pieces of those two valleys bottled up,'' he said, noting that there were Pakistani forces on the border to the south, opposition fighters in the valley and U.S. warplanes overhead.
``So we are watching this as carefully as we can,'' the defense official said. ``Whoever those al Qaeda are in there, they're not going anywhere. They're either going to surrender or fight to the death,'' he said.