A UK coroner presiding over the inquest of Alexander Litvinenko ruled Friday that he could not hear evidence about the Russian government's possible involvement in his poisoning, Agence France-Presse reported.
Litvinenko, a former KGB agent, died after he was poisoned with tea containing radioactive polonium-210 in a London hotel in 2006.
His widow Marina Litvinenko accused British coroner Sir Robert Owen of abandoning "his search for the truth about Russian state responsibility for her husband's death."
His wife and supporters believe his death was ordered by the Kremlin.
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The ruling means that the inquest into what caused Litvinenko's death could be scrapped. If that happens, it could be replaced with a hearing that would allow evidence to be presented in secret, the Huffington Post said.
Owen's ruling cited national security concerns and follows a request by the UK's Foreign Office to keep some evidence in the case private, the BBC wrote.
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