The Russian cargo ship Adler left a port outside St. Petersburg four days ago. It was heading north through the Sound on Saturday night when it suffered an engine failure.
The ship made a distress call and then anchored off the Kulla Peninsula.
"There is not much we can do if they have engine problems, but we have notified all authorities," says Marco Svensson, head of the Swedish Maritime Administration's monitoring center, to the newspapers.
The ship is owned by the company M Leasing LLC, which is on sanctions lists in the EU and the US. The reason is that the company's ships are said to have transported North Korean ammunition that Russia then used in the war in Ukraine.
The Coast Guard now has Adler under observation.
