Buenos Aires (AFP) - Argentina's military pushed forward Saturday with the hunt for a submarine that has been missing with 44 crew aboard for days, but said that bad weather has hampered the search.
There has been no contact with the ARA San Juan since early Wednesday, according to the navy, prompting Buenos Aires to launch an air and sea search for the missing vessel.
Nearly 80 percent of the search area has been scoured by ships and aircraft so far, Argentine navy spokesman Enrique Balbi told a news conference.
"The weather is bad. There is a storm with waves of six meters (nearly 20 feet)," Balbi said. "It really complicates the work."
And "at this stage of the search, there's really nothing that we can rule out," he stressed. So far, authorities say the likeliest hypothesis is that a power loss caused a communications loss.
Brazil, Britain, Chile, the United States and Uruguay took part in the aerial side of the search, said naval attache Oscar Filippi.
And the United States said it was sending rescue help.
The California-based Undersea Rescue Command was deploying two independent rescue assets -- including a pressurized rescue module -- to help in the hunt for the missing sub. They were expected on Sunday.
Argentine President Mauricio Macri said on his Twitter account that "we will do what is necessary to find the submarine as soon as possible."
The TR-1700 class diesel electric submarine had been returning from a routine mission to Ushuaia near the southernmost tip of South America, to its base at Mar del Plata, around 400 kilometers (250 miles) south of Buenos Aires.
Among those on board is Argentina's first female submarine officer, 35-year-old weapons officer Eliana Krawczyk.
The San Juan is one of three submarines in the Argentine fleet.
Sixty-five meters long and seven meters wide, it was built by Germany's Thyssen Nordseewerke and launched in 1983.
It underwent a re-fit between 2007 and 2014 to extend its usefulness by some 30 years.