The Indonesian navy on Saturday said the submarine that went missing earlier this week had sunk and cracked opened, killing its 53 crew members onboard, AP reports.

Details: Navy Chief Yudo Margono reportedly shifted the status of its missing vessel from "sub miss" to "sub sank." Rescuers found some items from the 44-year-old KRI Nanggala-402 submarine, including Muslim prayer rugs and grease bottles to lubricate periscopes, according to The New York Times.

• Bodies of the crew members have not yet been found, Margono added.
• Items were found floating in a location where the sea is 930 yards deep, CNN notes. Sonar seemed to indicate the submarine sank well below what is referred to as “crush depth," the Times writes.
• It is still unknown how the submarine sunk, but experts say that the vessel's descent must have been quick since it did not give any indication of its whereabouts, per The Times.

What they're saying: Margono added that the condition of the items suggested the submarine had not exploded, but rather cracked likely due to pressure from being in deep waters, The Times reports.