Disapproving of General Tôn Thất Đính's handling of the Buddhist Uprising, South Vietnamese prime minister Nguyễn Cao Kỳ ordered an attack on his forces and ousted Đính from his post.

Tôn Thất Đính
Lieutenant General Tôn Thất Đính was an officer who served in the Army of the Republic of Vietnam (ARVN). He is best known as one of the key figures in the November 1963 coup that led to the arrest and assassination of Ngô Đình Diệm, the first president of the Republic of Vietnam, commonly known as South Vietnam.
Buddhist Uprising
The Buddhist Uprising of 1966, or more widely known in Vietnam as the Crisis in Central Vietnam, was a period of civil and military unrest in South Vietnam, largely focused in the I Corps area in the north of the country in central Vietnam. The area is a heartland of Vietnamese Buddhism, and at the time, activist Buddhist monks and civilians were at the forefront of opposition to a series of military juntas that had been ruling the nation, as well as prominently questioning the escalation of the Vietnam War.
Nguyễn Cao Kỳ
Nguyễn Cao Kỳ was a South Vietnamese military officer and politician who served as the chief of the Republic of Vietnam Air Force in the 1960s, before leading the nation as the prime minister of South Vietnam in a military junta from 1965 to 1967. Then, until his retirement from politics in 1971, he served as vice president to bitter rival General Nguyễn Văn Thiệu, in a nominally civilian administration.