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LONDON - British Prime Minister Tony Blair promised today that "no diplomatic or political barrier" would be allowed to hamper an investigation into the death of a former Russian spy killed by radiation poisoning.
He spoke as police said they were searching two more central London addresses in connection with the death of Alexander Litvinenko, after finding traces of radiation at several sites where the former agent turned Kremlin critic had been.
Blair said the case was "very serious" and he would discuss it with Russian President Vladimir Putin in person if necessary.
"I haven't spoken to President Putin but I will do so at any time that is appropriate," Blair said. "There is no diplomatic or political barrier in the way of (the) investigation going wherever it needs to go."
"It obviously is a very serious matter and we are determined to find out what happened and who is responsible."
Significant amounts of radioactive Polonium 210 were found in the body of Litvinenko. He died on Thursday, accusing Putin of ordering his slow, agonising death.
He had received British citizenship just weeks earlier.
Police are treating his death as suspicious.
The Kremlin denies any involvement but the Litvinenko case has fuelled tensions between London and Moscow.
A post mortem will be carried out on Friday under secure conditions to avoid possible radioactive contamination.
Mario Scaramella, an Italian KGB expert who met Litvinenko the day he became ill, is under British police protection and is undergoing medical tests, an Italian senator told Reuters.
Sen. Paulo Guzzanti said Scaramella, who has advised an Italian parliamentary commission on Soviet-era espionage, told him by telephone on Tuesday he was being kept in a castle.
"He said 'Listen, they are treating me like the Prince of Wales'. I'm in a castle, can you believe it? They gave me ... escorts and bodyguards," Guzzanti said.
Held in safe house
Police refused to confirm Scaramella was under protection or being interviewed. His exact whereabouts were unclear.
Radiation was found at the sushi restaurant where Litvinenko met Scaramella on November 1 and traces have also been detected at several more sites, including Litvinenko's home, a hotel he visited, the offices of Russian tycoon Boris Berezovsky and the offices of Erinys, a security and risk management company.
London police said they were also searching the Sheraton Park Lane Hotel Piccadilly and another London address.
Berezovsky said he had complete faith in police and said he was "deeply saddened" at his friend's death.
Eight people have been sent for precautionary radiological tests, the Health Protection Agency said.
Russia's nuclear chief said he doubted the Polonium 210 which apparently killed Litvinenko had been stolen from Russia.
"The Polonium that is produced in Russia for export ... is controlled very strictly, there is one producer and so it is under very strict control in accordance with all international agreements," Sergei Kiriyenko said at a briefing.
There is frenzied speculation in British and Russian media about possible motives for killing Litvinenko. Some link it to his reported probes into Russian oil company Yukos and into last month's murder of Russian journalist Anna Politkovskaya.
- REUTERS
