2/ Polygon Media reports that senior figures among Russia's vory – its criminal elite – have lent their support to Russia's war in Ukraine. This is a major change in attitude for the vory, who are traditionally anti-authority.

Influential members – 'authorities' – of at least 10 criminal gangs have died in the war, as this map shows. They include men who have been convicted of robbery, extortion and murder, and in some cases were serving decades-long prison sentences.

3/ When the Wagner Group began recruiting prisoners, the criminal elite – the 'thieves in law' (vor v zakone) – were initially hostile due to traditionally antagonistic relationships between the vory and state authorities.

Attitudes changed after Shakro Molodogo (Zakhar Kalashov), the most senior vor currently imprisoned, urged convicts to join Wagner. His appeal was "broadcast on prison TV in the Kostroma, Vladimir, Magadan and Novosibirsk regions immediately after Putin's New Year address."

4/ Olga Romanova of the 'Russia Behind Bars' prisoners' rights group says: "Thieves' traditions have absolutely changed under Putin and thanks to him, in his 20 years, prisons are no longer divided into 'red' [run by the Federal Penitentiary Service] and 'black' [run by thieves].

"The world of thieves has merged with the world of the bosses. Shakro Molodogo is linked to the head of the Investigative Committee, [Alexander] Bastrykin - they are one gang", she says.