Indonesian authorities have asked neighboring countries for help over the disappearance of the submarine, Reuters reported.
The crew of the KRI Nanggala 402 submarine stopped communicating on Wednesday 21 April. Representatives of the Indonesian naval forces told Reuters that the submarine was conducting training torpedo tests in the area of Bali and did not get in touch at the agreed time.
According to TASS, the Indonesian Navy is searching for 53 people on board, seeking help from Singapore and Australia. KRI Nanggala-402 was produced in Germany in 1981. It is one of the submarines operated by the Indonesian Navy, CNN Indonesia reported.