They added there is no evidence to suggest the death is linked to the incident in Salisbury, where a former Russian spy Sergei Skripal and his daughter Yulia were poisoned with nerve agent which the United Kingdom government believes came from Russia.
Police said the death was not linked to the poisoning of Sergei Skripal and his daughter in Salisbury.
Counter-terror police said it was in charge of the probe "as a precaution because of associations that the man is believed to have had", a spokesman said.
An exiled Russian who was friends with an oligarch that fell out with Vladimir Putin has been found dead in Britain.
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He was escorted off the White House grounds before he was allowed to collect his belongings, even leaving without his jacket, the Journal reported.
The Met said officers believe they know who the man is, but he is yet to be formally identified. A post-mortem examination will be held in due course.
Glushkov was a close friend and business associate of Boris Berezovsky, the Russian oligarch who was found dead at his ex-wife's home in 2013.
In the 1990s, Glushkov worked for the state airline, Aeroflot, along with Berezovsky's LogoVaz auto company.
Glushkov received political asylum in London and gave evidence in Berezovksy's court case against Chelsea owner Roman Abramovich in 2011.
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A passenger bus crashed Tuesday morning on eastbound Interstate 10 at mile marker 57 near the Alabama/Florida line. Rescuers used every piece of equipment on every truck to reach them, Mack said: "This is what we call an all-out".
Mr Berezovsky was himself found dead on a bathroom floor at his home in southern England in 2013 with a scarf around his neck. His death was not treated as suspicious, but his friends were not convinced and a coroner later recorded an open verdict.
Glushkov, whose body was found last night at home in New Malden, South West London, had been caged for five years for money laundering while deputy director of Aeroflot.
Glushkov had said at the time that he did not believe Berezovsky died of natural causes.
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The new regulator will be capable of "holding the bottom line to prevent systematic financial risk", the parliament document says. China is restructuring the responsibilities, roles and powers of its state institutions to make them more efficient.