Civilian casualties occur when civilians are killed or injured by non-civilians, mostly law enforcement officers, military personnel, rebel group forces, or terrorists. Under the law of war, it refers to civilians who perish or suffer wounds as a result of wartime acts. The term is generally applied to situations in which violence is committed in pursuit of political goals. During periods of armed conflict, there are structures, actors, and processes at a number of levels that affect the likelihood of violence against civilians.