Kille in action (KIA or K. I. A.) is a casualty classification generally used by militaries to describe the deaths of their own forces by other hostile forces, or by "friendly fire" during combat. The United States Department of Defense (DOD) says that those declared KIA need not have fired their weapons but have been killed due to hostile attack. KIA's do not come from incidents such as accidental vehicle crashes and other "non-hostile" events or terrorism. KIA can be applied both to front-line combat troops and to naval, air, and support troops.