Indonesian rescuers searching for a submarine that went missing with 53 people on board found an oil spill on Wednesday near where the vessel dived, authorities said.
The 44-year-old submarine, KRI Nanggala-402, was conducting a torpedo drill when it failed to relay the results as expected, a navy spokesman said.
An aerial search found an oil spill near the submarine’s dive location and two navy vessels with sonar capability have been deployed to assist in the search.
Australia has offered assistance in the desperate mission to locate the submarine which is believed to have disappeared in waters about 95 kilometres north of Bali.
The vessel has not been seen or heard from since Wednesday when it was participating in a training exercise north of the popular tourist island.
"This is very distressing," Foreign Minister Marise Payne said on Thursday.
"The Australian Defence Force will work with defence operations in Indonesia to determine what we may be able to do.
"We will go to the support of our neighbour in any way we can."
The submarine was carrying 49 crew members, its commander and three gunners.
Oil spill could be signal from submarine crew
The vessel lost contact after being granted clearance to dive and could have sunk to a depth of between 600 and 700 metres.
The submarine was built to sustain pressure at a maximum depth of about 250 metres, according to officials.
The oil spill found on the surface could also mean there was damage to its fuel tank or could also be a signal from the crew, the navy said.
The military chief will hold a media briefing to share further information about the search later on Thursday from Bali.
Military analyst Soleman Ponto said it was too early to determine the fate of the submarine.
“We don’t know yet whether the communication equipments were broken or the submarine has sunken. We have to wait for at least three days,” he said.
The 1395-tonne KRI Nanggala-402 was built in Germany in 1977, according to the defence ministry, and joined the Indonesian fleet in 1981.
It underwent a two-year refit in South Korea that was completed in 2012.
Indonesia in the past operated a fleet of 12 submarines bought from the Soviet Union to patrol the waters of its sprawling archipelago.
But now it has a fleet of only five including two German-built Type 209 submarines and three newer South Korean vessels.
Indonesia has been seeking to modernise its defence capabilities, but some of its equipment is old and there have been deadly accidents in recent years.
with Reuters, AAP
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