Ukrainian resistance in Russian-occupied Ukraine
When Russia invaded Ukraine in early 2022, it occupied vast portions of the country, having already occupied parts of the Donetsk and Luhansk oblasts as well as the entirety of Crimea since the beginning of the Russia-Ukraine war in 2014. Partisan groups began to be organized in mid-2022.
Source: Wikipedia — Ukrainian resistance in Russian-occupied Ukraine (CC BY-SA 4.0)