Just spoke with a recently retired Umba and Kandalaksha procecutor. Asked him about what happens to foreigners caught in the “no foreigner” zones such as Umba or Sredny/Rybachy peninsula. The answer was that such cases have been extremely rare and that no consequences beyond a small fine and 2-3 hours at the police station can be expected. The fact that these areas are not clearly marked takes most of the blame off the offender, he said. But remember his was retired! And the trend in the last few years has been towards “tightening the nuts”. But my impression based on the conversation is that getting into these zones is not such a big deal.