William Calley Jr., the only American soldier convicted for his role in the My Lai Massacre during the Vietnam War, has passed away at the age of 80. According to reports from American media, Calley died on April 28 at a hospice center in Gainesville, Florida. The Washington Post was among the first to report on his death, referencing his death certificate. Further details surrounding the circumstances of his death are not yet available.

The My Lai Massacre, in which several hundred Vietnamese civilians were killed, has become a symbol of American misconduct during the Vietnam War. In 1969, there were more than half a million American soldiers stationed in Vietnam to combat the South Vietnamese Viet Cong guerrilla fighters. Calley’s conviction — the only one among 25 men originally charged in connection with the massacre — also illustrates the rarity with which the United States has held its own citizens accountable for abuses committed during foreign military operations.

In March 1968, Calley, who was a lieutenant in the U.S. Army, led Charlie Company on a mission to confront Viet Cong fighters. Instead of facing resistance, the soldiers massacred 504 civilians, predominantly women, children, and elderly men. The killings took place in My Lai and a nearby community, where soldiers later testified before a commission of inquiry that the abuses included gang rapes, shelling bomb shelters filled with civilians, and stabbing with bayonets.

In 1971, Calley was convicted of the murders of 22 individuals. He was sentenced to life in prison but served only three days after then-President Richard Nixon ordered a reduction of his sentence. Calley spent three years under house arrest.

The My Lai Massacre took a year to come to light in the United States, significantly illuminated by the publication of photographs of dead civilians taken by war photographer Ron Haeberle, along with the testimonies of soldiers who witnessed the events. A clearer understanding of the extent of American abuses in Vietnam took decades to uncover. In 2006, the Los Angeles Times reported, based on declassified military documents, that at least 320 incidents of abuse had been committed by American forces in Vietnam, including at least seven other massacres between 1967 and 1971 that collectively resulted in more than 137 civilian deaths.

In total, only 57 American soldiers were brought before a court-martial, with just 23 convicted, and all those convicted received light sentences, according to the newspaper. After his conviction, Calley lived in Columbus, Georgia, and worked at a jewelry store owned by his father-in-law. He later moved to Atlanta, where he largely avoided public attention.

In 2009, Calley broke his silence about the massacre and expressed regret for the Vietnamese people who were killed, as well as for their families and the American soldiers involved. However, he maintained that he was merely following orders, which was also his defense throughout the trial. He referred to the massacre as a mistake.