A series of incidents and charges bring relations between Cambodia, South Vietnam, and the United States to a low point. Cambodia under Prince Norodom Sihanouk had tried to maintain its neutrality in the growing conflict between Saigon and the Communists in Vietnam, but the country became a sanctuary for Viet Cong and North Vietnamese forces fighting the Saigon government. Sihanouk, not strong enough to prevent the Communists from using his territory, came under increasing political and military pressure from the United States and South Vietnam.
In this incident, South Vietnamese planes strafed a Cambodian village; when Cambodia protested, Saigon replied by reiterating its accusation that Cambodia was providing refuge for Viet Cong forces that were attacking across the border into South Vietnam. On October 22, the United States charged that Cambodian troops crossed over into South Vietnam and seized an U.S. officer advising South Vietnamese forces. On October 25, the officer's body was recovered just inside South Vietnam, and Cambodia was accused of placing the body there to allow the rescue force to be fired on. The next day, Cambodians shot down a U.S. Air Force C-123 cargo plane, loaded with ammunition for a Special Forces camp; eight U.S. servicemen aboard were killed. By October 28, the United States admitted that the plane had strayed over Cambodian territory by mistake, but argued that such incidents arose because of the poorly defined border and the activities of the Viet Cong in the area.
Despite the charges and threats from Prince Sihanouk and U.S. losses in personnel and planes, neither side pursued the matter. However, the use of Cambodia as a sanctuary by the Communists remained a contentious issue; in 1970, President Richard Nixon ordered U.S. and South Vietnamese forces to attack the sanctuaries in what became known as the Cambodian Incursion.