Boris Abramovich Berezovsky deadStrangled? Hanged? autoerotic asphyxiation? Or was he murdered by the secret services (British or Russian). Either side might have wanted him dead - to prevent him from revealing (possible) UK involvement in the Litvinenko murder or providing evidence of Putin's corruption (past or present); who knows - to speculate is to get sucked into the strange, deluded and paranoid world of conspiracy theorists; its pointless.
But it was own machinations, his muddying of waters, a lover of intrigue, a conspiracy merchant diminished his credibility as critic of Vladimir Putin and his increasingly authoritarian regime in Russia. His analysis of Putin might have been largely correct but his argument was tarnished by his hubris and desire for revenge against his erstwhile protégée.
Berezovsky loved the cut and thrust of Russian politics; loved having power, influence and control - perhaps more so than his great wealth - and has been described as his playing politics as a game of chess where only he is allowed to move the pieces. He was the embodiment of the wild 1990s, a former mathematician who made a great fortune through Russia's privatisation program, widely regarded as being corrupt. He was close to the Yelstin family, became a close advisor to Boris Yeltsin and reportedly played a key part in the rise of Vladimir Putin as Yeltsin's successor as Russian president. However, once Putin became president, Berezovsky was deprived of his influence and his control - his fall was spectacular.
He was exiled in London to avoid corruption charges, and an inevitable prison sentence in Russia, and became obsessed with revenge on Vladimir Putin. It would be of no surprise to me that he hand in the Litvinenko poisoning. Possibly a convoluted attempt at implicating the Russian authorities that backfired.