TEMPO.CO, Jakarta - President Joko Widodo (Jokowi) vowed to continue search and rescue efforts for personnel on board the KRI Nanggala-402 submarine, that was earlier declared "subsunk" as the submarine has sunk in the waters near Bali.

"They are the best sons of the nation, the best patriots, guardians of the country's sovereignty. All of the best efforts in search for them and to rescue them have been and will continue to be carried out," the President said in a press statement broadcast by the Presidential Secretariat, on Sunday.

The President appealed for all Indonesians to pray for the 53 submarine crew and to wish strength and fortitude for their families.

"This disaster come as a shock to all of us, not only to the families of all 53 personnel, the Hiu Kencana (Submarine Corps) personnel, and the Navy, but to all Indonesians. All of us are extending our deep condolences especially to the families of the personnel on board," he said.

Indonesian Military Commander Air Marshal Hadi Tjahjanto in a press conference in Bali on Saturday (April 24) said that the status of the submarine has been changed from "submiss" (missing submarine) to "subsunk" after a 72-hour search effort.

The operations on Saturday marked the third day of search and rescue efforts since KRI Nanggala-402 was declared missing in the waters north of Bali. The early hours of Saturday also marked the end of the limit of oxygen reserve for the crew, that could last 72 hours, if the submarine is on total blackout.

The Indonesian Navy's Chief of Staff, Admiral Yudo Margono, has said oxygen supply on KRI Nanggala-402 might suffice for five days, if the missing submarine has not experienced a power blackout.

Contact with KRI Nanggala-402 was lost during live torpedo training exercises off the tourist island on Wednesday.

The search for the submarine was focused on nine locations in the northern waters of Bali, about 40 kilometers from the Celukan Bawang coast in Buleleng district, after rescuers found oil spills and detected a strong magnetic force about 50 - 100 meters under the water’s surface.

Margono said the submarine is expected to have moved about 2 miles from its diving location.

The Indonesian military has deployed 21 warships, including those with sonar detection capability for underwater tracking. The warships include KRI Rigel-933, KRI Rimau-724, and the KRI Alugoro-405 submarine.

Some countries have also deployed their vessels for the search mission, including MV Swift Rescue from Singapore, MV Mega Bhakti (Malaysia), HMAS Ballarat and HMAS Sirius (Australia), SCI Sabarmati (India), and a Poseidon aircraft (the US).

The Indonesian Police and the National Search and Rescue Agency (Basarnas) have deployed ships, remotely operated underwater vehicles (ROV), and drones for the missing KRI Nanggala-402 submarine search.

Read: House Speakers Appeals Rescuers to Evacuate Sailors of KRI Nanggala-402

ANTARA