All aboard missing Argentine sub believed to be dead, family of missing sailor says A sound consistent with an explosion was detected during the search.

 -- Family members of the 44 sailors aboard a missing Argentine sub were told that their loved ones were believed to be dead, one of the family members told ABC News on Thursday.

Itati Leguizamon, whose husband, German Suarez, was aboard the submarine, the ARA San Juan, said the families were given the grim news.

Outside the ship's destination in Mar del Plata, Argentina, where family members gathered, a brother of one of the missing sailors was heard screaming, "They killed my brother!"

The news came as Argentine naval officials said that a sound detected during the desperate search for the sub, which vanished last week in the southern Atlantic Ocean, was consistent with an explosion.

The vessel was last heard from Nov. 15, and officials feared that it would run out of oxygen soon.

According to the Argentine navy officials, the sound, described as "consistent with a nonnuclear explosion" that was "abnormal, singular, short, violent" was detected three hours after the last known communication.

The sound, which originated about 270 miles east of the Gulf of San Jorge in the southern part of the country, was picked up by U.S. sensors and international agencies that are capable of detecting nuclear explosions.

According to the officials, the noise's source is in an area with a radius of 77 miles and possible depths of 650 to 10,000 feet.

The officials said that they do not believe the sound resulted from an attack or terrorism and that there was an indication of an electrical fault in the vessel on the morning of the last known communication.

According the officials, the sub should be largely in one piece even if there was an explosion, because a hull breach at such depths would result in the vessel's implosion.

Rescuers had been searching a 186,000 square mile area off the coast, and rough weather had hampered their efforts.

The vessel was en route to Mar del Plata from a base in Ushia, Argentina.