JAKARTA: Debris believed to be from Indonesian submarine KRI Nanggala 402 which went missing on Wednesday was found amid traces of an oil spill in the waters off Bali today.

Indonesian Navy (TNI) Commander Hadi Tjahjanto said the fragments, items and traces of the oil spill were located in an area where the sea was 850 metres deep.

The status of the submarine had been changed from "submissed" to "subsunk", he said in a press conference streamed on TNI's official YouTube channel (Puspen TNI).

"Early this morning (3 am) was the deadline of life support in the form of oxygen (reserves) availability on the KRI Nanggala 402," he said. 

Among the items found by a search team were a torpedo tube straightener, a cooling pipe, an orange bottle, prayer mats and periscope grease/lubricant. 

The submarine with 53 crew members was reported to have lost contact at 4.25 am on Wednesday during a torpedo training exercise off Bali, which also involved 21 TNI ships, five fighter jets and another submarine.

-- BERNAMA