Remember that something like 15% of the population in "Russia" is Muslims, almost entirely in places forcibly annexed into its' empire by Moscow. Including 50% of the population of
KAZAN, the namesake city on the Volga of one of our most prolific Putin promoters. Chechens especially resent rule by Moscow, and have done stuff like this before. Could it be ISIS? Yes it could.
What is NOT is Ukraine. No military or economic payout to be had. Muslims are insane, driven by their religion. Ukrainians are not.
False flag by Putin? Wouldn't rule it out. We'll see how it all plays out.