Roughly 15,000 combat-trained guerrillas, mostly Saudi and Gulf Arabs, Chechens and Pakistanis, make up the al Qaeda forces in Afghanistan. They are well funded, and get money from Gulf bank accounts brought by courier across the border with Pakistan. Other fighters or "Mujahideen" have been traced in Bosnia, Kosovo, Uzbekistan, Chechnya and Albania. About 10,000 fighters are now understood to have "returned home" to Yemen and Saudi Arabia, to await further assignment. The more sophisticated have been "sleepers" in Europe and North America.