Indonesia’s military on Sunday April 25, officially said all 53 crew members from a submarine that sank last week are dead after the search teams located the vessel’s wreckage on the ocean floor.

The grim announcement comes days after Indonesia said the 43-year-old German-made submarine, KRI Nanggala-402, was considered sunk, not merely missing, but did not state whether the crew was dead.

Officials previously said the KRI Nanggala 402’s oxygen supply would have run out early Saturday, three days after the vessel went missing off the resort island of Bali.

Wreckage from the KRI Nanggala-402 was found Sunday on the bed of the Bali Sea at 850m.

The navy said the diesel-powered submarine may have experienced a loss of battery power and was unable to return to the surface. There was only enough oxygen for the crew to survive for up to 72 hours.

‘It is possible that during static diving, a blackout occurred so control was lost and emergency procedures cannot be carried out and the ship falls to a depth of 600-700 metres,’ the FT reported.

Speaking to reporters on Sunday, Air Chief Marshal Hadi Tjahjanto said: ‘We received underwater pictures that are confirmed as the parts of the submarine, including its rear vertical rudder, anchors, outer pressure body, embossed dive rudder, and other ship parts.

“With this authentic evidence, we can declare that KRI Nanggala 402 has sunk and all the crew members are dead,” Tjahjanto said.

An underwater robot equipped with cameras documented the lost submarine lying in at least three pieces on the ocean floor at a depth of 838 meters (2,750 feet), said Adm. Yudo Margono, the navy’s chief of staff.

Indonesia’s President Joko Widodo delivered his condolences in a televised address Sunday.

“All Indonesians convey deep sorrow for this tragedy, especially to all of the families of the submarine’s crew. They are the best sons of the nation, patriots guarding the sovereignty of the country,” Widodo said.