KABUL - Late Tuesday night, four helicopters carrying 50 Afghan special forces commandos touched down just outside a Taliban compound on Afghanistan's western edge. Intelligence collected by U.S. and Afghan forces indicated the buildings were being used as a prison, holding dozens of Afghan security forces.

Middle-class Afghans turned jihadists have assisted the Islamic State group’s expansion from its stronghold in Afghanistan’s restive east to Kabul, analysts say, helping to make the capital one of the deadliest places in the country.