Following the Tonkin Gulf Incident US Naval forces in Vietnam were assigned to four major duties - Operation Sea Dragon, Operation Market Time, Operation Sea Lords and Naval Gunfire Support. The primary purpose of Sea Dragon forces was the interception and destruction of water borne logistic craft (WBLC), which ranged in size from large self propelled barges down to small junks and sampans. US Navy advisers were assigned to the Vietnamese Navy and, in late 1961, US Navy minesweepers assisted Vietnamese Navy (VNN) ships to carry out patrols near the Demilitarized Zone (DMZ).
