Underwater movement detected at missing Indonesian submarine's last submarine By IANS | 4 Views Indonesian authorities claim to have located crashed plane's black boxes. Image Source: IANS News Jakarta, April 22 : The Indonesian Army detected underwater movement at 2.5 knots around the last location of the submarine Nanggala-402 missing during a torpedo firing exercise in waters north of Bali Island, according to an official source on Thursday. "The contact then lost, so there is still not enough data to identify that it was a submarine," said the military spokesperson Achmad Riad. A helicopter and two military vessels also found the oil spill and the smell of diesel fuel at several different locations, but it is not yet possible to conclude that this is submarine fuel, Riad added.