John le Carré has nothing on this mysterious tale of a former aide to Russian President Vladimir Putin found dead in a Washington, D.C. hotel room.

Billionaire Mikhail Y. Lesin died from a heart attack, Russian media said in November when his body was found slumped in the bathroom.

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But on Thursday, the district's cheif medical examiner's office said Lesin died from blunt force injuries to his head. The office did not explain the length of time from Lesin's death to its test results being announced, The New York Times reported.

The medical examiner's office also said Lesin's body had blunt force trauma to the neck, torso, arms and legs.

Metropolitan Police Department spokesman Lt. Sean Conboy, declined to provide additional comment. Andrew Ames, a spokesman for the F.B.I. in Washington, also declined comment, the paper reported.

Lesin was the founder of the Russia Today TV channel and a key Putin ally nicknamed the "Bulldozer," who helped shape the country's media portrayal of the strongman president.

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Speculation swirled after Lesin's body was discovered, with tabloids saying he had been a FBI informant and owed money to big businesses in Russia.

Leslin served as a Kremlin adviser during Putin's second term.

In 2014, U.S. Sen. Roger Wicker, a Mississippi Republican, called for a federal investigation over Leslin's purchase of multiple Califoria homes worth tens of millions, alleging possible corruption.

Leslin's death is under investigation by local and federal authorities. The medical examiner's office did not provide information about the circumstances of his death.

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