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LONDON - Former Russian spy Alexander Litvinenko - poisoned in London three weeks ago - has died, the hospital treating him has said.
The 41-year-old critic of Russian President Vladimir Putin has said he fell ill after meeting two Russians at a hotel.
Britain's anti-terrorism police were called in to investigate the case after doctors determined last week his illness was caused by poison.
Litvinenko's friends accuse the Kremlin of orchestrating a plot to poison him, but Russia has dismissed the allegation as "nonsense".
If Moscow were found to have had a hand in his poisoning there could be far-reaching diplomatic consequences. It would be the first such incident known to have taken place in the West since the Cold War.
Dr Geoff Bellingan, clinical director of critical care at London's University College Hospital had earlier told reporters shadows seen on Litvinenko's x-rays were believed to be caused by a chemical given as part of his treatment, not by poison, and therefore did not offer clues as to how he fell ill.
Litvinenko, who became a British citizen, co-authored a book in 2002 entitled "Blowing up Russia: Terror from Within", in which he alleged Federal Security Service (FSB) agents co-ordinated apartment block bombings in Russia that killed more than 300 people in 1999. Officials blamed the bombings on Chechen rebels.
He had been investigating the killing of Russian journalist Anna Politkovskaya, also a vocal critic of Putin, who was gunned down at her Moscow flat on October 7.
- REUTERS