同士討ち
Friendly fire or fratricide is an attack by a military force on friendly or neutral troops while attempting to attack the enemy. Examples include misidentifying the target as hostile, cross-fire while engaging an enemy, long range ranging errors or inaccuracy. Accidental fire not intended to attack the enemy, and deliberate firing on one's own troops for disciplinary reasons, is not called friendly fire, and neither is unintentional harm to civilians or structures, which is sometimes referred to as collateral damage. Training accidents and bloodless incidents also do not qualify as friendly fire in terms of casualty reporting.