The Gulf of Tonkin incident, also known as the USS Maddox incident, was an international confrontation that led to the United States engaging more directly in the Vietnam War. It involved either one or two separate confrontations between North Vietnam and the United States in the waters of the Gulf of Tonkin. The original American report blamed North Vietnam for both incidents, but the Pentagon Papers, the memoirs of Robert McNamara, and NSA publications from 2005 proved material misrepresentation by the US government to justify a war against Vietnam. On August 2, 1964, the destroyer USS Maddox, while performing a signals intelligence patrol as part of DESOTO operations, was pursued by three North Vietnamese Navy torpedo boats of the 135th Torpedo Squadron. Maddox fired three warning shots and the North Vietnamese boats then attacked with torpedoes and machine gun fire. Maddox expended over 280 3-inch (76.2 mm) and 5-inch (127 mm) shells in a sea battle. One U.S. aircraft was damaged, three North Vietnamese torpedo boats were damaged, and four North Vietnamese sailors were killed, with six more wounded. There were no U.S. casualties. Maddox "was unscathed except for a single bullet hole from a Vietnamese machine gun round."