London - Two months after the world watched the real-life thriller of the radioactive poisoning of Alexander Litvinenko, the mystery surrounding the death of the former Russian spy has thickened.
While Scotland Yard in London remains tight-lipped about its investigations and the Russian authorities are playing tough over their cooperation, the tale of Litvinenko has captivated the media industry.
US actor Johnny Depp has apparently agreed to play the 43-year-old Russian in a film by Warner Bros, who have snapped up the rights to an as yet unpublished book on Sasha's Story by London-based New York Times writer Alan Cowell.
Livinenko's own book, Blowing Up Russia, originally published in the US in 2002 but banned by Moscow, is due for re-release.
Meanwhile, British health authorities reported that, out of 596 people tested since Litvinenko's death, 120 have tested positive for contamination by small amounts of the radioactive isotope polonium- 210.
Only 13, the authorities said, were deemed to have a 'small health risk' resulting from the contamination.
Those trying to make sense of the web of allegations, counter- charges and speculation surrounding the case of Litvinenko have been rebuffed and frustrated by an ever-growing net of confusion.
The results of an autopsy of Litvinenko performed after his death in a London hospital on November 23 have never been published.
A BBC television investigation this week claimed that Litvinenko, who came to Britain in 2000, was likely to have been the target of 'multiple' poisoning attempts.
The programme said a first attempt on his life was probably made as early as October 16 last year during a meeting with former KGB-men Andrei Lugovoi and Dimitri Kovtun, who have both denied any involvement.
The encounter took place in the same Itsu sushi bar in central London where Litvinenko met Italian contact Mario Scaramella on November 1, the day he fell ill.
But his widow, Marina, told the BBC's Panorama programme that she was sure her husband was poisoned with a cup of tea he had when he met the two Russians at London's Millennium Hotel later on November 1.
'He said it was tea already served, on the table, and he just took this cup of tea, and he didn't finish it at all, and how he later said the tea wasn't very tasty, because it was cold.'
Marina Litvinenko, 44, again implicated Russian President Vladimir Putin in her husband's death.
'I cannot say exactly that Putin killed my husband but I can say that Putin is behind everything that happens in Russia,' she said.
Kremlin spokesman Dimitry Peskov fired back, 'If she says Russia has killed Sasha, she's a liar for these words.'
While the publicly-held positions of both sides remain entrenched, there appear to be attempts to break a diplomatic stalemate that has been holding up the progress of British-Russian investigations.
The news Monday that Russian prosecutors had halted their case against London-based oligarch Boris Berezovsky, a close associate of Litvinenko, but also a man the Russians desperately wanted to have extradited for fraud, appeared to signal a turning point.
According to analysts in London, the Russian move could facilitate a visit by Russian investigators to interview Berezovsky in London - something that has been a prime Russian demand for allowing Scotland Yard detectives to make a second trip to Moscow in the Litvinenko affair.
© 2007 dpa - Deutsche Presse-Agentur 
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