The San Juan has been missing off the coast of Patagonia for more than two days, and the navy denies that communication was lost after a fire on board
Argentina's navy has launched a huge search-and-rescue operation for a military submarine with 44 crew members that has been missing off the coast of Patagonia for more than two days.
The last radio contact with the San Juan submarine was on Wednesday, when it was 430km off the coast of the southern province of Chubut, in the area of San Jorge bay, a naval spokesman said on Friday.
The spokesman, Enrique Balbi, told local television that as there was no indication of problems from the submarine, it could not yet be termed lost.
"The latest official and reliable information is that the submarine has not yet been found. It's not that it's lost: to be lost you'd have to look for it - and not find it," he said. A tracker aeroplane and navy ships were scouring the area in search of the missing vessel, he said.
An initial search in an area around the sub's last known position, about 430km off the south-eastern Valdés peninsula, provided no clues.
Balbi said an initial search was hampered "because it was carried out at night and in bad meteorological conditions prevailing in the area of operations".
The three navy ships and two aircraft flying rotations had "already swept 15% of the search area", Balbi told reporters.
The vessel had not activated its emergency beacon, he said.
The navy denied a press report that there may have been a fire onboard.
"We are investigating the reasons for the lack of communication," Balbi said. "If there was a communication problem, the boat would have to come to the surface."
The diesel-powered 66-metre-long Class TR 1700 San Juan is one of the Argentinian navy's three submarines. It was bought from Germany in 1985 and underwent a refit between 2007 and 2014 to extend its usefulness by 30 years.
It was on a voyage from the southernmost city of Ushuaia to the naval base of Mar del Plata when contact was lost.
Adm Gabriel González, chief of the Mar del Plata base, said the vessel had sufficient food and oxygen. "We have a loss of communications; we are not talking of an emergency," he said.
Relatives of some of the crew members were at the base awaiting word of the search.
"We are praying to God and asking that all Argentinians help us to pray that they keep navigating and that they can be found," said Claudio Rodríguez, whose brother is a crew member.
"We have faith that it's only a loss of communications," he told local television.
Among those onboard is Argentina's first female submarine officer, Eliana Krawczyk, a 35-year-old weapons officer.
"Let us pray that nothing has happened to any crew member. At sea they are all brothers, and a submarine carries more risk than a ship," her father, Eduardo, told Todo Noticias TV.
The governments of the US, UK and Chile have offered satellites and ships to aid in the search, according to Argentina's foreign ministry.