Major Matthew Đặng Sỹ (July 29, 1929 – November 11, 2006) was an officer in the Army of the Republic of Vietnam. He acquired a degree of infamy for ordering his soldiers to open fire on a crowd of Buddhists demonstrating against a ban on the Buddhist flag, leading to the Huế Vesak shootings in which nine people died. This sparked the Buddhist crisis and downfall of Ngô Đình Diệm. Early life Born in the province of Thừa Thiên, Huế, Sy Dang came from a long line of devout Roman Catholics, including Michael Dinh-Hy Ho, one of the Vietnamese Martyrs. He attended a Lasallian school, graduated from National Military Academy of Da Lat as first Lieutenant. His father was a captain for the local national guard unit. At age 14, Sy Dang ventured as an interpreter for the local French garrison. He tried the prospect of being a Christian Brother, like his mother's brother, but found he was not suited for a "pious", teaching life. He decided to follow a military career. He married Cam De Nguyen at the age of twenty-one. She converted to Roman Catholicism; the couple had ten children. Military career After his graduation from the Vietnamese National Military Academy in Da Lat and having attended the U.S. Infantry Center & School at Fort Benning, Sy Dang quickly progressed to the rank of major, assigned to the First Infantry Division and was named as deputy Governor and Security Chief, in charge of Thừa Thiên and Huế city. While in this position, he was embroiled in the midst of political unrests such as the Huế Vesak shootings. He ordered his men to open fire on the unarmed demonstrators, and nine were murdered in the ensuing chaos. . The trial of Đặng Sỹ As Deputy Governor in charge of Huế's security, Major Sy Dang was held responsible for the deaths of nine Buddhists. Many accounts, which included official CIA reports and U.S. State Department weekly reports, indicated that Major Đặng took direct actions that caused these deaths. There are other minority accounts, which suggested Major Đặng was at the right time and place for a set-up by third party with interests in seeing the Diệm regime fall. Journalists Arthur Dommen and Ellen Hammer speculated that an American serviceman and a handful of CIA operatives orchestrated the entire affair. Marguerite Higgins and an independent United Nations investigative team reported on