At about midnight, six "Swifts," special torpedo boats used by the South Vietnamese for covert raids, attack the islands of Hon Me and Hon Ngu in the Tonkin Gulf. Although unable to land any commandos, the boats fired on island installations. Radar and radio transmissions were monitored by an American destroyer, the USS Maddox, which was stationed about 120 miles away.
The South Vietnamese attacks were part of a covert operation called Oplan 34A, which involved raids by South Vietnamese commandos operating under American orders against North Vietnamese coastal and island installations. Although American forces were not directly involved in the actual raids, U.S. Navy ships were on station to conduct electronic surveillance and monitor North Vietnamese defense responses under another program, Operation De Soto. The Oplan 34A attacks played a major role in events that led to what became known as the Gulf of Tonkin Incident. On August 2, North Vietnamese patrol boats attacked the Maddox, which had been conducting a De Soto mission in the area. Two days after the first attack, there was another incident that still remains unclear. The Maddox, joined by destroyer USS C. Turner Joy, engaged what were thought at the time to be more attacking North Vietnamese patrol boats. Although it was questionable whether the second attack actually happened or not, the incident provided the rationale for retaliatory air attacks against the North Vietnamese and the subsequent Tonkin Gulf Resolution. The resolution became the basis for the initial escalation of the war in Vietnam and ultimately the insertion of U.S. combat troops into the area.