055 Brigade. According to military analyst Ali Jalali, the 055 Brigade was only 400–600 strong, but its ties to bin Laden made it politically important. The foreign fighters included Arabs as well as Kashmiris, Chechens, Uzbeks, and Uyghurs. Several hundred officers from Pakistan's ISI were stationed in Afghanistan advising the Taliban. By mid-October, approximately 10,000 Pakistani volunteers crossed the border to augment the Taliban's forces. The volunteers were mostly madrasa students, some as young as 14. Both sides primarily used Russian military equipment. The Northern Alliance had 14.5mm heavy machine guns, Russian artillery, T-72 tanks, and BMP-1 armored vehicles retrofitted with rocket pods from Soviet combat helicopters. Dostum's Uzbeks used horses for transportation. The Northern Alliance had 18 helicopters and three fixed-wing planes, used mostly for logistical purposes. The Taliban's equipment was similar to that of the Northern Alliance, and they also had Stinger missiles donated by the United States to the mujahideen during the Soviet–Afghan War. They relied on pickup trucks for mobility and operated as a "motorized light force." They had about 40 combat aircraft, operated by ex-PDPA pilots. Both sides had a history of human rights abuses: Uzbeks and Hazaras had "massacred hundreds of Taliban prisoners and killed Pashtun villagers in the north and around Kabul", and the Taliban killed 5,000–8,000 civilians after they captured Mazar-i-Sharif in 1998. Afghanistan also faced a serious humanitarian crisis in 2001 due to drought; according to the United Nations, 5 million Afghans were in need of humanitarian aid that year and 3.8 million could not survive without UN food aid. Prelude to the invasion On the morning of September 11, 2001, al-Qaeda carried out four coordinated attacks on the United States, employing four hijacked jet airliners. The attacks killed almost 3,000 people and injured more than 6,000 others. By the early afternoon of September 11, the CIA had confirmed that al-Qaeda was responsible for the attack. The Taliban condemned the attacks, but Mullah Omar issued a statement denying bin Laden's involvement. Although bin Laden eventually took responsibility for the 9/11 attacks in 2004, he initially denied having any involvement. One of bin Laden's strategic goals was to draw the US into a costly war in Afghanistan, so it could be defeated just as the Soviet Union had been. Diplomatic and political activity On the evening of September 11, President Bush stated the US would respond to the attacks and would "make