An Argentinean submarine has lost contact in the South Atlantic with 44 crew on board, military authorities said on Friday.
The ARA San Juan was carrying out a surveillance mission in Argentina's exclusive economic zone near Puerto Madryn, around 1,400 km south of Buenos Aires.
Argentina's naval commander for the Atlantic, Gabriel Gonzalez, told media on Friday that "48 hours ago", radioelectrical communication was lost with the submarine.
The last communication with the craft happened on Wednesday and navy spokesman Enrique Balbi denied that it had been found, after press reports suggested it had.
Answering rumors about the submarine, Balbi said that news of a fire on board was "not official information. There may have been a technical fault, there is no communication yet".
The foreign ministry also issued a statement saying that "the governments of Chile, the United States and the United Kingdom have offered logistical support and exchange of information in this humanitarian search".
Three planes, four ships and one helicopter are searching the area for the missing submarine.
The ARA San Juan is a TR-1700 submarine made in Germany, which joined the Argentinean navy in 1985.