The suspect, Aleksei Frenkel, is the former head of a private bank that Kozlov had closed down three months before he was shot dead in September.
Frenkel's lawyer, Igor Trunov, said Frenkel was formally charged today with organizing Kozlov's murder.
Frenkel says he is not guilty. He was detained last week and a court on January 15 sanctioned his arrest.
Kozlov had led a campaign against money laundering in the banking system. A total of seven suspects have been arrested in connection with his murder.
Demonstrators in Moscow carry a coffin with a television in it to protest government control over broadcasting (TASS file photo)
DO RUSSIANS LIKE THEIR GOVERNMENT? During a briefing at RFE/RL's Washington office on November 15, Richard Rose, director of the Center for the Study of Public Policy at the University of Aberdeen, discussed the results of 14 surveys he has conducted since 1992 on Russian public opinion about democracy and the country's development. He discussed the implications of these opinions for relations with the West and for Russia's 2008 presidential election.
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