A sound detected near the last known location of an Argentine navy submarine carrying 44 crew members is believed to have come from an explosion.
Enrique Balbi, spokesman for the Argentine navy, told reporters at a news conference Thursday that officials have found evidence showing that the abnormal sound, which was detected 30 miles north of the submarine's last-known location, was "singular, short, violent and non-nuclear" and "consistent with an explosion," the Associated Press reported.
Balbi also said that officials do not know what caused the explosion and that there's no evidence the vessel had been attacked.