friendly fire
noun /ˌfrendli ˈfaɪə(r)/
/ˌfrendli ˈfaɪər/
[uncountable]- in a war, if people are killed or injured by friendly fire, they are hit by a bomb or weapon that is fired by their own side
- Several soldiers were killed in friendly fire due a mistake by allied forces.
Oxford Collocations DictionaryFriendly fire is used before these nouns:- incident