This group seem to be Russians who were fighting in Ukraine against Russia.
They have done a raid over the border once before and returned to Ukraine.
Denys thinks it is most likely that they will return to Ukraine.
One day I think they will at least try to liberate Russia, and it is better to try that while most of the Russian troops are occupied elsewhere,
IMO Russia is initially unlikely to use their main tactic of mass artillery against their own civilian towns, so they need to retake the territory with troops and tanks, and that might put the tanks in some danger.
I'm very interested to see how far they go and how long they stay... and if they strike again at a future date, perhaps elsewhere.
There must be plenty of similar border areas that need to be properly defended.