- Rescuers searching for the Indonesian submarine say they must stay "optimistic."
- Oxygen levels were due to run out on the missing sub.
- The Indonesian submarine disappeared during a training exercise this week.
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Rescuers searching for the Indonesian submarine that disappeared during a training exercise this week say they must stay "optimistic" as oxygen levels were due to run out on the missing sub.
"We ask for prayers from all Indonesians that the 53 people [aboard] will be safe," Indonesian Navy spokesperson Julius Widjono told CNNIndonesia.com.
Authorities said earlier that the KRI Nanggala-402 submarine likely had little air supply left – and the deadline to find the 53 crew members before the oxygen on the vessel was expected to run out has since passed.
On Thursday, Indonesian officials said the sub would likely run out of oxygen early Saturday local time – or Friday afternoon EST. The 40-year-old submarine was only equipped with a 72-hour supply of oxygen.
The sub disappeared on Wednesday morning after missing a routine check-in during a torpedo drill near Bali. Military vessels from the US, India, Australia, Malaysia, and Singapore have since joined the search for the missing vessel.
The Associated Press reported Friday local time that Indonesian Navy chief of staff Adm. Yudo Margono said an object with "strong magnetic resonance" had been found, but authorities have not confirmed whether the find was the sub or something else.
Search teams also found oil slicks on the ocean, a sign that the submarine's fuel tanks may have been breached.
If the submarine sank to a depth of 600 to 700 meters (2,000 to 2,300 feet), as the Indonesian navy fears, the hull could have collapsed.