"An anomalous, singular, short, violent and non-nuclear event consistent with an explosion", occurred shortly after the submarine's last communication, navy spokesman Captain Enrique Baldi told a news conference in Buenos Aires.
As the search for the missing Argentina submarine has entered a "critical phase", the country's navy said Wednesday it was investigating an unusual noise detected in the South Atlantic hours after it last communicated with the vessel.
After eight days of uncertainty amid search and rescue efforts by more than a dozen countries, the relatives received word from the Argentine navy that an explosion had occurred aboard the ARA San Juan on November 15 in the area near the submarine's last known position.
The ARA San Juan search location straddles the edge of the continental shelf, where ocean depths vary, but reach as deep as 3,000 metres.
The vessel had seven days of oxygen supply, meaning the crew would be running low if it had not been able to surface.
No sign of the Argentine submarine lost in the South Atlantic since November 15 has been found despite a massive worldwide search effort, while families of the 44 crew members face the increasing likelihood that their loved ones will never return.
Balbi said teams have been searching for the missing submarine in waters of the San Jorge Gulf, about 430 kilometers (268 miles) from the coast.
There was no evidence of any attack and no information on the cause of the noise, Balbi said.
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The media blackout was followed by suspension of services of popular social networking sites - Facebook , Twitter and YouTube . The siege played havoc with the more than half million commuters who daily travel between Islamabad and Rawalpindi.
Itati Leguizamon, whose husband is among the missing, told reporters, "They did not tell us they were dead, but that is the logical conclusion". They did not give an explanation.
"At this point, the truth is I have no hope that they will come back", Maria Villareal, mother of one crew member, told local television on Friday morning, according to Reuters.
"We don't have any saint left to pray to; we have no one left to ask".
'I feel like I'm waiting for a corpse, ' she said.
"Until we find the submarine and have all the information", Macri said on Friday, "we are not going to speculate on who is at fault".
A member of the U.S. Navy, aboard the Boing P-8A Poseidon aircraft, looks down at the the South Atlantic Ocean during the search for the ARA San Juan submarine missing at sea, Argentina November 22, 2017.
It appeared to be the first time since the Falklands conflict in 1982 that an RAF plane had landed in Argentina, although the UK Ministry of Defense would only characterize it as the first time in a "very long time".
The U.S. Navy said it had deployed unmanned underwater vehicles, or "mini-subs" equipped with sonar, to join the search.