Thai submarines saw service throughout World War II, but saw no combat. Two of them did serve an unconventional role during the war. On 14 April 1945, five months before the Japanese surrender, Bangkok's Samsen and Wat Liab Power Plants were bombed by the Allies, leaving the city without electricity. In response to a request from the Bangkok Electricity Authority, the "Matchanu" and "Wirun" anchored at the Bangkok Dock Company and served as power generators for one of Bangkok's tram lines.