Indonesia’s military has officially admitted there is no hope of finding survivors from a submarine that sank and broke apart last week with 53 crew members aboard.

Search teams have located the vessel’s wreckage on the ocean floor, it added.

The grim announcement comes a day after Indonesia said the submarine was considered sunk, not merely missing, but did not explicitly say whether the crew was dead.

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

“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,” military chief Hadi Tjahjanto told reporters in Bali on Sunday.

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

The navy previously said it believes the submarine sank to a depth of 600-700 metres (2,000-2,300ft), much deeper than its collapse depth of 200 metres (655ft), at which point water pressure would be greater than the hull could withstand.

An underwater robot equipped with cameras and deployed by Singaporean vessel MV Swift Rescue provided the images, while the Indonesian vessel KRI Rigel had scanned the area where the submarine was believed to have sunk using multibeam sonar and a magnetometer, Tjahjanto said.

The cause of the disappearance was still uncertain.

The navy had previously said an electrical failure could have left the submarine unable to execute emergency procedures to resurface.

An American reconnaissance plane, a P-8 Poseidon, landed early on Saturday and had been set to join the search, along with 20 Indonesian ships, a sonar-equipped Australian warship and four Indonesian aircraft.

The German-built diesel-powered KRI Nanggala 402 had been in service in Indonesia since 1981 and was carrying 49 crew members and three gunners as well as its commander, the Indonesian Defence Ministry said.

Indonesia, the world’s largest archipelago nation with more than 17,000 islands, has faced growing challenges to its maritime claims in recent years, including numerous incidents involving Chinese vessels near the Natuna islands.