<P> The massacre, which was later called "the most shocking episode of the Vietnam War", took place in two hamlets of Sơn Mỹ village in Quảng Ngãi Province . These hamlets were marked on the U.S. Army topographic maps as Mỹ Lai and Mỹ Khê . </P> <P> The U.S. Army slang name for the hamlets and sub-hamlets in that area was Pinkville, and the carnage was initially referred to as the Pinkville Massacre . Later, when the U.S. Army started its investigation, the media changed it to the Massacre at Songmy . Currently, the event is referred to as the My Lai Massacre in the United States and called the Sơn Mỹ Massacre in Vietnam . </P> <P> The incident prompted global outrage when it became public knowledge in November 1969 . The massacre increased to some extent domestic opposition to the U.S. involvement in the Vietnam War when the scope of killing and cover - up attempts were exposed . Initially, three U.S. servicemen who had tried to halt the massacre and rescue the hiding civilians were shunned, and even denounced as traitors by several U.S. Congressmen, including Mendel Rivers, Chairman of the House Armed Services Committee . Only after thirty years were they recognized and decorated, one posthumously, by the U.S. Army for shielding non-combatants from harm in a war zone . Along with the No Gun Ri massacre in Korea eighteen years earlier, Mỹ Lai was one of the largest single massacres of civilians by U.S. forces in the 20th century . </P> <P> Charlie Company, 1st Battalion, 20th Infantry Regiment, 11th Brigade, 23rd Infantry Division, arrived in South Vietnam in December 1967 . Though their first three months in Vietnam passed without any direct contact with North Vietnamese - backed forces, by mid-March the company had suffered 28 casualties involving mines or booby - traps . </P>

Who was in charge of the my lai massacre