As the search continues for the ARA San Juan submarine carrying 44 officers, forces from around the world have united around a common cause.
Satellite calls that had raised hopes of finding a submarine that has been lost at sea for five days did not come from the 44 crew members on board, the Navy said Monday, complicating an international rescue effort that has already been hindered by stormy weather.
The ARA San Juan, a German-built diesel-electric sub, made its last contact on Wednesday. The A multinational air and sea search is under way with help from countries including Brazil, Britain, Chile, the United States and Uruguay.
US Southern Command has deployed a Navy P-8A Poseidon patrol and reconnaissance plane with a crew of 21, along with a NASA P-3 research aircraft, and other equipment and personnel.
The US Navy has deployed two unmanned underwater vehicles that use a sonar system to create an image of large sections of the sea floor.
Britain's Royal Navy said it had sent the HMS Protector, an Antarctic patrol ship.
Although the crew has enough food, oxygen and fuel to survive about 90 days on the sea's surface, they only have enough oxygen to last seven days if submerged, Navy spokesman Enrique Balbi said.
Admiral Gabriel González of the Mar del Plata Naval Base confirmed Monday that the submarine had reported an electrical problem Wednesday and was returning to the base when it went missing in the South Atlantic.