An Argentine military submarine with 44 crew members on board was missing at sea in the South Atlantic on Friday, prompting a massive search to locate the vessel which may have suffered a communication error, a navy spokesman said.
The ARA San Juan submarine was in the southern Argentine Sea, 432 km (268 miles) from the Patagonian coast when it gave its last location two days ago.
"When the submarine has no communication with land, it has to go to the surface, and so visual or radar detection is what is important," Argentine naval spokesman Enrique Balbi told reporters. "The search in the area remains hot."
The navy began an air and sea search on Thursday. On Friday afternoon, Argentina's foreign ministry said that the U.S., British and Chilean governments had offered logistical support and exchanges of information to assist with the search.
A Chilean aircraft with the ability to search during the night was en route to assist, Chile's Foreign Minister Heraldo Munoz said.
Balbi said the submarine, which left the southern city of Ushuaia for Mar del Plata, both in Argentina, had food supply for several days and would likely continue its journey despite communication problems.