Berezovsky was part of Boris Yeltsin's inner circle in the latter years of his presidency, and became deputy secretary of Russia's security council.
He acquired his fortune in the 1990s after the privatisation of state assets following the collapse of Soviet Communism.
The businessman survived a number of assassination attempts, including a bomb in his car that decapitated his chauffeur.
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Essex Police say that they can't comment on Martin Goldberg's death, but there were indications of an attempt to destroy evidence.
Police say indecent images of children have been found at the home of a deputy head teacher, who was recently found dead.
Essex Police say pictures of boys undressing have been discovered in the home of a teacher who's been found dead.