Platon Lebedev, one of Mr Khodorkovsky's main partners, was arrested, and probes into Yukos were launched.

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He and his business parton Platon Lebedev who were jailed in 2005 on tax evasion and other fraud charges.

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The downturn in Mr Khodorkovsky's fortunes became obvious in July 2003, when Platon Lebedev, his partner and now co-defendant, was arrested.

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