After the fall of Kabul and Kandahar, al-Qaeda elements including Bin Laden and other key leaders withdrew to Jalalabad, Nangarhar Province, from there they moved into the Tora Bora region of the White Mountains, 20 km away from the Pakistan border - where there was a network of caves and prepared defenses used by the mujahideen during the Soviet-Afghan War. Signal intercepts and interrogation of captured Taliban fighters and al-Qaeda terrorists pointed towards the presence of significant numbers of foreign fighters and possible HVTs in and moving to the area; instead of committing conventional forces, higher echelons of both the White House and the Pentagon took the decision to isolate and destroy the al-Qaeda elements in the area with the US SOF supporting locally recruited AMFs (Afghan Militia Forces) - due to misplaced fear of replicating the Soviets experience in the area.