A recent Times (UK) article reported that the British Ministry of Defence stated that the Russian Army may have units instructed to fire on Russian soldiers attempting to retreat during the current war in Ukraine, a tactic reminiscent of WW2.
Unfortunately it's behind a paywall, but the "readable" preview bit states...
Russia’s army has “probably” instructed special units to fire on retreating soldiers in Ukraine in an echo of Stalinist practice during the Second World War, the Ministry of Defence has claimed.
“Due to low morale and reluctance to fight, Russian forces have probably started deploying ‘barrier troops’ or ‘blocking units’,” it said in an intelligence update. “These units threaten to shoot their own retreating soldiers in order to compel offensives and have been used in previous conflicts by Russian forces.”
The Ministry of Defence tweeted a similar claim:
However, when someone says "probably" they can often mean anything from just themselves supposing as far as having evidence that this is very likely.
A search around the 'net reveals articles stating different levels of certainty but pointing back to the same "probably" quote from the MOD, without offering any further evidence.
So my question is, is there anything other than this quote, or any elaboration on this quote (or what is meant by "probably" in this case) to indicate the likelihood that Russia are shooting their own retreating soldiers?