The Indonesian Navy submarine Nanggala imploded and sank in the Bali Sea, resulting in the deaths of all 53 people on board. KRI Nanggala (1980): KRI Nanggala (402), also known as Nanggala II, was one of two Cakra-class Type 209/1300 diesel-electric attack submarines of the Indonesian Navy. It sank following an implosion in April 2021. April 21, 2021. Wiki link