Authorities in Indonesia were trying to locate a missing submarine on Wednesday.
The KRI Nanggala-402 submarine stopped responding in the early morning, local media reported, citing defense officials.
Indonesian National Armed Forces (TNI) Commander Marshal Hadi Tjahjanto told national paper Kompas that the submarine disappeared in waters about 60 miles (95 kilometers) north of the island of Bali.
“Just when the dive permit was given, after being given the clearance, contact was immediately lost,” he told the paper.
It is one of five submarines owned by the Indonesian armed forces and was built in West Germany in 1979.
Indonesia has requested the help of Australia and Singapore in finding the submarine. Republika reported that the TNI had deployed all ships with underwater search capabilities to help find the missing vessel.
The military said 53 people were on board and that it was involved in torpedo drills when it went missing.