Then it was revealed that the intended procurement was an improved Jang Bogo-class submarine, the members of which are now in service as the Nagapasa class.

A Royal Australian Navy transport vessel, HMAS Kanimbla, was to serve as an INTERFET command post.

An Indonesian Cakra-class submarine was conducting a routine patrol duties in the Timor Sea, when its sonar detected several unidentified surface ships moving towards Dili.

At that point, the commander of Kanimbla communicated with the Australian government regarding the situation, and Canberra contacted Jakarta to request permission for the INTERFET vessels to enter Indonesian waters and set course to Dili.

[8] On 21 April 2021, the Indonesian Navy announced that Nanggala, with 53 sailors on board, had failed to report after a SUT torpedo live fire exercise in the Bali Sea.

[12] On 24 April, Indonesia officially declared that the submarine had sunk, following the retrieval of objects believed to have been parts of Nanggala, including a torpedo straightener and prayer mats.

"With the authentic evidence we found believed to be from the submarine, we have now moved from the sub miss phase to sub sunk", Navy Chief Yudo Margono has said.

"Based on the evidence, it can be stated that the KRI Nanggala has sunk and all of its crew have died," Marshal Hadi Tjahjanto told reporters.