By Kyrill Dissanayake
Mr Litvinenko fell ill after a meeting at a London restaurant
Reports that the dissident former Russian security officer Alexander Litvinenko had been poisoned in London first surfaced in Russia's mainstream media on 11 November.
The independent radio station Ekho Moskvy was the first broadcaster to break the story, quoting a report published on a Chechen rebel website.
Since then coverage of the poisoning in the mainstream media has been confined to a small number of outlets.
Most noticeably for a media landscape dominated by television, Russia's three main TV networks seem to have steered clear of the story.
There appears to have been no mention of Mr Litvinenko in any of the main news bulletins or discussion programmes on state-controlled Channel One and Rossiya, nor on NTV, which is owned by the energy giant Gazprom.
Brief reports were, however, broadcast on the corporate-owned Ren TV channel and the business channel RBK TV.
The lack of television coverage came as no shock to Ekho Moskvy's editor-in-chief, Alexei Venediktov.
"It's not at all surprising that there's silence on television, it's understandable," he told listeners to his phone-in programme on Sunday.
The launch of an investigation by British police had led to "confusion" in the Russian authorities, he said.
Ekho Moskvy is the only mainstream Russian broadcaster to have aired regular reports on Mr Litvinenko's poisoning.
Since the British media latched onto the story on Saturday, the station has aired comments from another prominent Kremlin critic to have been granted asylum in Britain, Chechen rebel envoy Akhmed Zakayev, as well as Alex Goldfarb, a friend of Mr Litvinenko who helped him with his asylum application six years ago.
Earlier, Ekho Moskvy commentator Yuliya Latynina had spoken of the likely fallout from the case.
"This is a fairly key milestone, which undoubtedly alters the image of Russia in the outside world," she said.
Press coverage, meanwhile, has been minimal, with most papers ignoring Mr Litvinenko's ordeal.
The only title to have dealt with the story in detail is the Kommersant broadsheet, which carried its own report as well as comments from a number of Russian politicians and former security service officers.
The paper also quoted the exiled Russian tycoon Boris Berezovsky, another fierce critic of the Kremlin, who visited Mr Litvinenko in hospital on Friday.
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