"In the autumn of 1941 several Russian submarines left their home bases to patrol the Baltic Sea. Several of them never returned. One of them has now been found, blown up into large pieces, southeast of Öland," the Swedish Armed Forces (Försvarsmakten) said in a statement.
The wreck was discovered earlier this autumn following reports in the Russian media that Swedish civilian divers had found a submarine wreck southeast of Öland.
The wreck was localized by the submarine rescue ship HMS Belos, which also managed to take pictures of the sunken Soviet sub.
According to the Swedish military, the wreck is likely that of S-6, a Soviet submarine that went missing in September 1941.
The wreck was found near the "Wartburg minefield" in international waters, but within Sweden's economic zone.
While it remains unclear exactly what may have caused S-6 to go down, an open hatch provides some clues as to what may have happened.
"Boats at the time often sailed on the surface in order to quickly flee and/or to recharge their batteries," Commander Christian Allerman of the Swedish Navy said in a statement.
The Swedish military theorized that the submarine simply sailed right into the German minefield and was blown up.
The wreck consists of two main pieces, with the bow section coming to rest about 20 metres north of the stern section, which was found next to a torpedo-like object.
The images captured by the HMS Belos also show Russian text on the wreck, as well as the Soviet hammer and sickle.
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In June 2009, divers found the wreck of the S-2, another Soviet sub sunk by mines in January 1940 with some 50 crew members on board, in waters further
north between Sweden and Finland.