I live in a country which was occupied by Russia during Soviet era. They immigrated here tons of people from all over the Russia and satellites, and after the end of occupation, those immigrants remained. Civilians, you say. However, ca 90% of them still speak only Russian, take in only Russia's propaganda and are acting just the way Russia's media tells them to think and act. Keep their kids in the same information space.

They are the 5th column. Ready to support new invasion and act as enemy's combatants.