Key witnesses in the Alexander Litvinenko investigation are missing, with their families claiming that they fear for their lives.
The sudden disappearance of a number of leading figures linked to the affair will make it even harder for British detectives, whose inquiry has now spread across five countries.
Interpol joined the hunt for the murderer yesterday, saying that it hoped to exchange information coming from Britain, France, Italy, Germany and Russia.
Scotland Yard was struggling to gain access to vital witnesses with former associates of Litvinenko claiming that they are too scared to come forward.
Evgeny Limarev, who told the former KGB officer that he was on a death list just hours before he was poisoned, was reported to have fled his home in the French Alps, where he was under police protection. Before his disappearance, he said that British detectives wanted to question him about the origins of a hitlist that included Litvinenko’s name among the targets being hunted by a team of former Russian agents working across Europe.
In Moscow, nine detectives from Scotland Yard’s counter-terror squad are seeking a further interview with the two Russian businessmen who met Litvinenko in a London hotel where police now believe that he was poisoned.
Both men are still being kept at a clinic run by the Federal Medico-Biological Agency of Russia, which is sealed off.
Russian authorities describe Dmitri Kovtun as a target for the assassin who killed Litvinenko. British police still call him a significant witness, while prosecutors in Hamburg say they are investigating him for allegedly illegally handling the radioactive polonium-210, which they believe was smuggled from Russia through Germany to Britain, foxnews.com reports.
Dmitri Kovtun said on Tuesday he must have picked up traces of polonium from the murdered man when he met him in London in mid-October.
That is well before Litvinenko fell ill, on November 1.
A German prosecutor has said Russian businessman Dmitry Kovtun, who met Litvinenko on the day he fell ill, could be a possible suspect in the case.
Kovtun denies any part in Litvinenko's poisoning. German prosecutors are investigating him on suspicion of illegally handling radioactive material after traces of polonium were found in properties he used in Hamburg, and British and Russian investigators have also interviewed him in Moscow.
Litvinenko died in London on November 23 after receiving a lethal dose of radioactive polonium-210. He accused Russian President Vladimir Putin of ordering his killing, although the Kremlin has denied being involved.
The ensuing mystery has sparked a cross-border investigation stretching from London to Moscow and Hamburg and generated a string of conspiracy theories, Reuters reports.
Prepared by Alexander Timoshik
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