With the Taliban growing more violent and adding checkpoints near Kabul's airport, an all-volunteer group of American veterans of the Afghan war launched a final daring mission on Wednesday night dubbed the "Pineapple Express" to shepherd hundreds of at-risk Afghan elite forces and their families to safety, members of the group told ABC News. Moving after nightfall in near-pitch black darkness and extremely dangerous conditions, the group said it worked unofficially in tandem with the United States military and U.S. embassy to move people, sometimes one person at a time, or in pairs, but rarely more than a small bunch, inside the wire of the U.S. military-controlled side of Hamid Karzai International Airport. The Pineapple Express' mission was underway Thursday when the attack occurred in Kabul.