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LONDON - British police investigating the poisoning of Alexander Litvinenko will go to Moscow to speak to witnesses who met the former Russian spy in London shortly before his death, a police source said.
Nine detectives may fly to Moscow as early as today, while others have already visited the United States as part of the probe, the source said, speaking on condition of anonymity.
Interior minister John Reid said the probe into Litvinenko's mysterious poisoning with radioactive polonium 210 was set to broaden.
"The police will follow wherever this investigation leads, inside or outside of Britain," he told Sky TV.
From his deathbed, Litvinenko accused Russian President Vladimir Putin of ordering his slow and agonising death, which sparked a health scare in Britain and strained London's relations with Moscow.
The Kremlin denies involvement and has promised full cooperation with the British investigation. Other theories have centred on the possible involvement of rogue Russian agents.
The police source said the dead spy's meeting with Russian citizens at London's Millennium Hotel on November 1 -- the day Litvinenko fell ill -- was "of interest" but not necessarily the focal point of the police visit to Moscow.
Andrei Lugovoy, a former KGB agent, and businessman Dmitry Kovtun met Litvinenko at the Millennium Hotel. Lugovoy told British newspapers Litvinenko wanted to discuss a business opportunity and he had nothing to do with any attempt on Litvinenko's life.
The Observer reported today that British police officers had gone to Washington to interview a former KGB agent who said he had vital information about the case.
British authorities said last week that traces of radiation had been found at 12 sites and aboard planes that carried 33,000 passengers in the past month. Reid said there was no cause for concern over any health risk.
Mario Scaramella, an Italian contact of Litvinenko who was admitted to a London hospital after polonium 210 was detected in his body, said on Sunday he believed both he and Litvinenko had been poisoned because of secrets they shared. He said he had received a potentially lethal dose of polonium 210.
He did not accuse anyone of the poisoning or specify what kind of information Litvinenko had given him.
The London hospital treating Scaramella said however he remained well. "The results of his pathology tests to date remain normal. Further tests are being carried out today," a spokesman said on Sunday.
Scaramella, a KGB expert, met Litvinenko at a London sushi restaurant on November 1 to show him emails from a source warning their lives might be in danger.
Traces of polonium 210 were also found in the urine of Litvinenko's widow Marina, but Reid called the risk negligible.
British newspapers published a variety of theories about Litvinenko's death on Sunday. The Observer alleged Litvinenko had planned to make tens of thousands of pounds blackmailing senior Russian spies and business figures.
The Sunday Times said Putin had voiced anger at Britain's failure to gag Litvinenko in his final hours.
Reid dismissed the speculation. "It isn't a game of 'Cluedo'," he said, referring to a murder mystery board game.
- REUTERS