Alexander Litvinenko's grave illness is still a mystery
The case of Alexander Litvinenko, the former Russian secret service officer critically ill from alleged poisoning in London, has drawn comment in the Russian media, which had largely ignored the story for days.
Most are sceptical of his story, believing the Russian authorities would gain nothing from his death.
Friends of Mr Litvinenko suspect that the Federal Security Service (FSB) - his former employer - was involved in the "poisoning".
Vladimir Demchenko in Izvestiya says Mr Litvinenko is the "man they couldn't catch, with the twist that nobody is trying to catch him".
Killing Mr Litvinenko would only give exiled businessman Boris Berezovsky - a fierce critic of President Vladimir Putin - "a gift he could not buy with all the money in the world", he writes. That view is shared by several commentators.
An article in Moskovsky Komsomolets agrees that poisoning an exiled figure many years after he made his revelations would be a strange thing for any Russian agent to do.
Semyon Shapkin in Komsomolskaya Pravda is sceptical about Mr Litvinenko's story on the grounds of alleged inconsistencies and his closeness to Mr Berezovsky.
He dismisses the idea of a Kremlin plot, saying Mr Litvinenko poses no threat to Moscow and that the incident has further harmed Russia's already tarnished image in the West.
Another London-based ex-Soviet intelligence officer, Boris Volodarsky, is alone in openly accusing the FSB of poisoning Mr Litvinenko, in the English-language Moscow Times.
He says the secret service has been after Mr Litvinenko for years because of his "fierce and fearless mockery" of President Putin.
He doubts whether Mr Putin was aware of the alleged assassination plot, asking if the Russian leader is in control of his "squabbling entourage".
Mr Volodarsky concludes it is most likely a warning to Mr Berezovsky that living in London is no protection from the long hand of the FSB security service.
Kommersant's deputy editor Kirill Rogov reviews the accusations and counter-accusations from both sides, concluding there seems little benefit to Moscow in poisoning Mr Litvinenko.
He says the lasting effect of the scandal is to encourage a negative image of Russia's leaders in the West.
"The effect that Politkovskaya's murder and now an attempt on Litvinenko's life produced in the West reflects the accumulated impression about the current morals of the Russian elite and authorities over the past few years," he adds.
Journalist Anna Politkovskaya, another outspoken critic of the Kremlin, was shot dead in Moscow last month. Mr Litvinenko said he had been investigating her murder at the time he was poisoned.
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