BRITAIN: Scotland Yard's Counter Terrorism Command has now taken the lead in the investigation into the suspected deliberate poisoning of former Russian security agent Alexander Litvinenko in London.
That was confirmed last night as dramatic pictures were released showing the one-time KGB colonel ravaged by poison, having lost his hair and been reduced to a gaunt shadow of his former self, battling for life under armed guard in his bed at University College Hospital.
Mr Litvinenko and his friends claim he was the victim of a "state-sponsored" murder bid because of his outspoken opposition to president Vladimir Putin and his Moscow regime.
The former spy, who defected to Britain six years ago, fell ill at the beginning of the month after meeting a number of contacts separately over drinks followed by lunch in a London sushi bar.
He had been investigating the murder of Russian journalist Anna Politkovskaya, also an outspoken critic of Mr Putin and Russian policy in Chechnya, who was shot dead at her Moscow apartment building last month.
Clinical toxicologist John Henry of St Mary's Hospital said Mr Litvinenko became quite seriously sick after being poisoned by a potentially lethal dose of thallium, sometimes described as "the poisoner's poison".
Mr Henry explained: "It is tasteless, colourless, odourless. It takes about a gramme - you know, a large pinch of salt like in your food - to kill you."
The Kremlin dismissed as "sheer nonsense" claims it - or the successor to the KGB, the Federal Security Bureau (FSB) - had been involved in this attempt on the life of a British national on UK soil.
Spokesman Dmitry Peskov insisted: "We cannot comment on the very fact of what happened to Litvinenko. We do not consider it possible to comment on the statements accusing the Kremlin because it is nothing but sheer nonsense."
The Russian Foreign Intelligence Service, another of the successor agencies to the KGB, also issued a separate statement denying any involvement.
However, Oleg Gordievsky - the most senior KGB officer ever to defect to the UK - maintained the attempt to kill Mr Litvinenko had been "state-sponsored" and carried out by a Russian former colleague recruited by the FSB while in prison, who would probably have already returned to Moscow.
Faced with the possibility of a massive, unwanted and highly embarrassing diplomatic fallout with Moscow, the British government maintained its silence yesterday, pending the result of the police investigation. However, the London Times urged police to treat the case urgently as one of attempted murder.
Noting the man who successfully sought asylum in the UK had been "a thorn in the Kremlin's side because of his open opposition to President Putin", the paper's editorial said: "The suspicion must be, therefore, that his attempted murder was ordered by the Kremlin to silence him and to send out a chilling warning to other defectors and critics of the Kremlin."
Moscow might deny any connection with the poisoning, as Bulgaria for years denied it was behind the fatal umbrella stabbing of dissident Georgi Markov, but "no rogue security service" could be allowed to attempt the murder of Britons in their own country. "If a connection with the FSB is proved, Britain must, at the very least, make its anger felt," the paper said, concluding: "Britain's counter-intelligence is now occupied with the far greater threat of Islamic extremism. But it should not ignore behaviour reminiscent of a former, vicious cold war feud."
Moscow's denial came as Mr Litvinenko was returned to intensive care yesterday as a precaution. His friend Alex Goldfarb said he remained vulnerable to infection and doctors said he had a 50/50 chance of surviving the next three to four weeks.
Mr Goldfarb also admitted there was "no direct evidence" to support his allegation of Russian government involvement.