The ARA San Juan, an Argentine Navy vessel, was travelling to the coastal city of Mar del Plata on 15 November 2017 when contact with those on board was lost.
Crew members had been ordered to return to a naval base on the coast after the submarine’s captain said that water had entered the snorkel, causing one of the vessel’s batteries to short circuit.
He later said that the situation had been contained, but a few hours later an explosion was detected near the San Juan’s last known location.
The navy said that the blast could have been caused by a “concentration of hydrogen” triggered by the faulty battery.
Crew members only had a seven day supply of air when the San Juan disappeared.
Argentina gave up hope of finding survivors from the vessel after an international search, aided by 18 countries, ended without success.
Ocean Infinity, a private maritime company that can search and map the seabed, was then hired by Argentina’s government to find the submarine.
The navy said a remote operated submersible from the firm had made a ”positive identification” of the vessel thousands of feet below the ocean surface.
Rescuers found the San Juan just two days after families of the missing sailors held a commemoration event marking a year since the submarine disappeared.
Argentina’s president Mauricio Macri said the families should not feel alone, in remarks made on the anniversary.
He also declared an ”absolute and non-negotiable commitment” to find “the truth”.
The disappearance of the San Juan caused extensive debate over the state of the military in Argentina, which has one of Latin America’s smallest defence budgets relative to the size of its economy, following a series of financial crises in the country.
Argentina’s government dismissed the head of the navy in January during a probe into the submarine’s disappearance.
Federal police raided naval bases and other buildings the same month.
Additional reporting by agencies