KABUL, Aug 16 (Reuters) - U.S. and Afghan air and ground forces pounded al Qaeda militants for a second day on Thursday in the Tora Bora mountains close to the Pakistan border where Osama bin Laden once fled in the wake of the 2001 invasion. The steep slopes of the mountains are riddled with cave and tunnel complexes built by Afghan and Arab fighters during the 1980s struggle against the Soviet occupation and provide an ideal hideout for guerrilla fighters. "It is a joint operation conducted by Afghan and U.S. forces, divided by ground and air assets," said Captain Vaness Bowman, spokeswoman for U.S.-led coalition forces in Afghanistan. "Afghan and U.S. forces engaged al Qaeda and other violent extremist fighters in the eastern Afghanistan region in Tora Bora," she said, adding that the operation began on Wednesday. "I personally don't have any casualty reports at this time, but we do know that there have been substantial casualties." Three coalition soldiers were killed in a roadside bomb in the Khogiani district near Tora Bora on Sunday and a U.S. base in the area also came under rocket attack in the last few days. U.S. soldiers and Afghan militia forces launched a major assault on Tora Bora in late 2001 in pursuit of al Qaeda and its leader, Osama bin Laden, who was thought to be hiding in the mountain range after the toppling of the Taliban government. But U.S. military leaders allowed the Afghan militiamen to spearhead the assault and bin Laden managed to escape. Al Qaeda forces and their Taliban allies use the rugged and semi-lawless border region between Afghanistan and Pakistan to plan, train and launch attacks in both countries.
