Soldiers of the U.S. Army’s Charlie Company killed between 347 and 504 unarmed Vietnamese civilians, including women, children, and elderly people, in the hamlets of Mỹ Lai and Mỹ Khe. Some victims were raped and mutilated. The killings were covered up by the unit.
Journalist Seymour Hersh exposed the massacre. Lieutenant William Calley was convicted of murder; most other participants were not successfully prosecuted. The event became a symbol of the moral costs of the Vietnam War and contributed to public opposition.