According to reports, Indonesia's navy announced on Sunday that all 53 crew members of the missing submarine have died, and that search teams have discovered the vessel's wreckage on the ocean floor.
"We received underwater pictures that are reported as parts of the submarine, including its rear vertical rudder, anchors, outer pressure body, embossed dive rudder, and other ship parts," military chief Hadi Tjahjanto said on Sunday, four days after the vessel vanished off the coast of Bali's resort island.
"We may announce that the KRI Nanggala 402 has sunk and that all of the crew members are dead based on this authentic evidence," Tjahjanto added.
According to Adm. Yudo Margono, the navy's chief of staff, an underwater robot fitted with cameras discovered the missing submarine lying in at least three parts on the ocean floor at a depth of 2,750 feet.
According to earlier navy claims, this is much deeper than the submarine's collapse depth of 655 feet, at which point water pressure would be greater than the hull could withstand.
The cause of the submarine's demise is unknown.
The navy previously stated that an electrical malfunction may have prevented the submarine from performing emergency resurfacing procedures.
Emergency survival suits, which are usually stored in boxes, were discovered floating underwater, meaning that the crew may have attempted to put them on during the emergency, according to Margono.
The debris is 1,500 yards south of where the submarine last dove off Bali's northern coast, according to Margono.
The photographs of the wreckage were provided by the underwater robot deployed by the Singaporean vessel MV Swift Rescue, while the Indonesian vessel KRI Rigel searched the area where the submarine was thought to have sunk using multibeam sonar and a magnetometer, according to Tjahjanto.
Although the depth of the water poses a major obstacle, the navy expects to ultimately lift the debris and retrieve the dead, according to Margono.
In a televised address on Sunday, Indonesian President Joko Widodo expressed his condolences.
"All Indonesians are deeply saddened by this tragedy, especially the families of the submarine crew. They are the best sons of the land, patriots who protect the country's sovereignty "Widodo stated the following.
According to the Indonesian Defense Ministry, the German-built diesel-powered KRI Nanggala 402 had been in operation in Indonesia since 1981 and was carrying 49 crew members, three gunners, and its commander.