On Thursday, Argentina's navy announced that a sound detected during the search for a missing submarine is believed to have been an explosion, an ominous development in the search for the missing vessel. Navy spokesman Enrique Balbi said that the search will continue until there is certainty over the fate of the ARA San Juan. Balbi told reporters, “According to this report, there was an explosion. We don’t know what caused an explosion of these characteristics at this site on this date.” U.S.