(The Local) A Russian distress call prompted Sweden's hunt for "foreign underwater activity" in the Stockholm archipelago, newspaper Svenska Dagbladet (SvD) reports.
Swedish signals intelligence officials first heard an emergency call on Thursday evening, the newspaper said. Fourteen hours later, at around midday on Friday, a foreign vessel was spotted in the Stockholm archipelago.
Sweden intercepted further communications after it began its military operation in the waters off Stockholm, as encrypted messages were relayed between transmitters in the Stockholm archipelago and the Russian exclave Kaliningrad.
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