Updated at 3:25 p.m. ET
NATO in Afghanistan says it will lead an investigation into an airstrike in Kunduz this weekend that hit a Médecins Sans Frontières hospital, killing 22 people — an attack that the humanitarian organization, also known as Doctors Without Borders, has called "a war crime."
A U.S.-led airstrike on the northern Afghan city was carried out Saturday, but the circumstances surrounding it remain murky.