Kadryov has apparently just sent his forces to Rostov.

He is the lunatic who controls the Chechen fiefdom, sorry Republic, whose troops were used as blocking units (ie kill anyone from your own side who tries to retreat) in the early part of the war. They were also responsible for a lot of the atrocities carried out in the early part of the invasion.

So now we have the prospect of three factions of Russian psychopaths killing each other and destroying each other's stuff on Russian soil. Excellent.