Australia has joined the search for an Indonesian submarine missing off the coast of Bali.
An Australian frigate equipped with sonar systems and a submarine-hunting helicopter will reach the search area on Friday.
A support ship off the coast of Brunei will join the search early next week, replenishing other vessels with fuel, water and stores.
Fleet commander Mark Hammond said the two Australian ships would help expand the search area and extend the duration of the effort.
"My thoughts are with the submariners of KRI Nanggala, their families and the Indonesian people," Rear Admiral Hammond said.
"As always, we stand ready to assist our fellow mariners in the Indonesian Navy."
The Indonesian submarine went missing on Wednesday with 53 sailors on board.
The vessel was conducting a torpedo drill when it missed a scheduled reporting call.
It lost contact after being granted clearance to dive and could have sunk to a depth of between 600 and 800 metres, well below its safe operating levels.
The Australian Defence Force remains in close contact with Indonesia to determine if it can provide any further assistance.
Australian Associated Press
