The UDTs saw their first combat on 31 January 1944, during Operation Flintlock in the Marshall Islands. FLINTLOCK became the real catalyst for the UDT training program in the Pacific Theater. In February 1944, the Naval Combat Demolition Training and Experimental Base was established at Kīhei, Maui, next to the Amphibious Base at Kamaole. Eventually, 34 UDT teams were established. Wearing swim suits, fins, and dive masks on combat operations, these "Naked Warriors" saw action across the Pacific in every major amphibious landing including: Eniwetok, Saipan, Guam, Tinian, Angaur, Ulithi, Peleliu, Leyte, Lingayen Gulf, Zambales, Iwo Jima, Okinawa, Labuan, Brunei Bay, and on 4 July 1945 at Balikpapan on Borneo, which was the last UDT demolition operation of the war.