Stand up against, if not the Kremlin then still Russia's top military command, and your days are likely numbered.

There is certainly form in Russia for unpleasant ends.

Wagner boss 'passenger on crashed plane' - latest updates

Russia's aviation agency has confirmed Yevgeny Prigozhin, his deputy Dmitry Utkin and his head of security, Valery Chekalov, were on board the Embraer jet that crashed just north of Moscow.

If their deaths are confirmed, that is the top ranks of the mercenary group's leadership gone, in one fell swoop.

It is two months to the day since Prigozhin launched his short-lived mutiny in Moscow, calling his men off when they were halfway there after intense mediation from the Belarusian leader.

Vladimir Putin was confronted with one of the most dangerous moments of his presidency and he vowed vengeance, but never delivered.

Prigozhin seemed to be enjoying free passage around Russia and Belarus. Charges against him were dropped even as speculation raged that he would not and could not last long.

The last we saw of him was a video message from what appeared to be the African Sahel earlier in the week, promising in his words to make Russia "even greater" across all continents and Africa "even more free".

Clarity as to what exactly caused this plane to crash will most likely be a long time coming, if indeed we ever find out at all.

If Prigozhin was not on board then we would likely hear from him.

He is a man who courts public attention and would be quick to set the world straight - but even the Wagner-affiliated Telegram channels are now declaring him dead.

Read more:
Who is 'Putin's butcher Yevgeny Prigozhin?
What we know so far about the plane crash

Prigozhin's trolls, his caterers, his spin doctors and his mercenaries furthered the Kremlin's aims, across continents, for more than a decade but with his outspoken critique of Russia's armed forces, he trod a dangerous tightrope.

In the last weeks, his business empire has been dismantled and it appears he was being muscled out of his African dealings.

Whatever happened in the skies above Tver region, his apparent death will prove one thing - that no one is indispensable.