When the Taliban were ousted from power in Afghanistan in 2001, the hunt for Osama bin Laden began in earnest. One American in particular led the search. He was CIA commander, Gary Berntsen, who had been tracking the al-Qaeda leader for years. In December 2001 he ordered a small group of special forces soldiers and Afghan fighters into the White Mountains, close to the border with Pakistan, in the hope of cornering bin Laden in the caves of Tora Bora. But as Gary Berntsen tells Rebecca Kesby, in spite of heavy bombardment bin Laden managed to give them the slip.

(PHOTO: Local anti-Taliban fighters help US special forces in the assault on the White Mountains and Tora Bora cave complex in Afghanistan, December 2001. (Photo by Chris Hondros/Getty Images)