A submarine in the Argentina Navy's South Atlantica has gone missing. The 44-passenger submarine has no contact for three days.
President Morrisio Macri said that all national and international resources are being set up to find San Juan as soon as possible.
NASA's Research Plain has also been included in this search operation.
After disappearing 430 km (267 miles) from the beach, the UK and countries of this region have also offered help.
Argentine Naval spokesman Enrique Balby said in a news conference, "We are unable to find submarines, nor are they able to do any visual or radar communication."
Diesel-electric submarine was returning from its regular mission from Usavia, which is near the south of South America, located in southern Mar del Plata of Buenos Aires.
On Wednesday morning, the last contact was made from this submarine.
An Argentinian destroyer and two Corvette (small warships) combing operations are operating around the area of the last known situation of the south-eastern Valdez Peninsula.
But there is no clue about its whereabouts yet.
Balbi said, after no contact with the submarine, the rescue operation has been formally upgraded to the investigation and rescue process.
He said, "Despite the good amount of boats and aircraft involved in the search, the investigation has become difficult."
The task of rescue teams has been difficult with high winds and high waves. Balbi said that due to lack of talk with the ship for several hours, it became a matter of concern.
It seems that due to power cuts in the submarine, communication problems have occurred.
The Naval Protocol says that if the communication with the ship is not in place, then it should come back to the sea.
Balbi said, "We hope that it is on the seashore."
One German-built submarine from Argentina's new three submarines was inaugurated in 1983.
President Makari told that the government was in constant contact with the family of the group.
He wrote on Twitter, "We share their concerns with all the people of Argentina."
"We promise to use all national and international resources to find ARA San Juan submarines as soon as possible."
Balbi said that besides the long flying American NASA P-3 aircraft, the Argentine Air Force, the Hercules C-130 is also preparing to participate in the investigation.
Brazil, Chile, Uruguay, Peru and South Africa have formally offered assistance in search.