Hope turned to anger and despair for the families of 44 missing submariners Thursday after the Argentine navy shared news of a grim development. The navy said that a "hydro-acoustic anomaly" detected by the US Navy and a nuclear test-ban monitoring organization soon after the ARA San Juan was last heard from Nov. 15 was apparently an explosion, the BBC reports. Navy spokesman Enrique Balbi said the explosion was recorded near the sub's last known location and was "singular, short, violent, and non-nuclear." He said the cause of the apparent explosion is unknown and the search will continue until the vessel's fate is known. Relatives at the Mar del Plata base were seen collapsing in tears.
The sub, which had reported a battery failure, was last heard from close to where Argentina's continental shelf drops to depths the vessel could not have survived at, the Guardian reports. "If a submarine goes below its crush-depth, it would implode, it would just collapse," retired US Navy Capt. James H. Patton Jr. tells the AP. "It would sound like a very, very big explosion to any listening device." Relatives accused the navy of giving them false hope—and of sending their loved ones to die in an unfit vessel. "They sent a piece of crap to sail," said Itati Leguizamon, wife of sonar operator German Suarez. "They inaugurated a submarine with a coat of paint and a flag in 2014, but without any equipment inside."