TEMPO.CO, Jakarta - The searchers have found debris believed to be from the missing submarine in waters off Bali Island, Indonesian Navy Chief of Staff Admiral Yudo Margono said on Saturday, April 24.

"The condition of the 53 people aboard the KRI Nanggala-402 submarine cannot be determined," he told a press conference.

The search and rescue operation is faced with huge difficulties because of the depth of 850 meters under water. As a result, each procedure must be carried out properly, he said in Bali.

The submarine had suffered from cracks that caused several components to separate from it, said the navy chief of staff, adding that the cracks became bigger when the submarine dove deeper amid rising water pressure.

The Indonesian navy said on Saturday afternoon that it had raised the status of search for the missing submarine from SUBMISS to SUBSUNK. The decision came after they found some authentic evidence of debris believed to be from the KRI Nanggala-402, one of which looks like a torpedo tube.

The debris was found about 10 km away from the search area where no other boats had passed.

Indonesian National Armed Forces (TNI) chief Hadi Tjahjanto expressed sorrow over the sinking of the submarine.

"We all feel very sorrowful with this incident. And I would like to convey that to all the crew of KRI Nanggala and the soldiers on board ... I would like to express my deep concern," Tjahjanto said at the press conference.

"We together pray for the efforts of the process of this search. It can continue to be carried out and can get strong evidence," he said.

The German-made submarine lost contact after requesting diving permission to fire the Surface and Underwater Target Torpedo at 3:00 a.m. local time on Wednesday.

The vessel, delivered to Indonesia in 1981, carried 53 people aboard, namely 49 crew members, one commander, and three arsenal personnel.

The military said it would prepare an evacuation for any survivors from the submarine.

Read: Indonesian Navy Declares Missing Submarine Have Sunk

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