Secret service officer charged in Politkovskaya’s murder case
Mr Ryaguzov is accused of passing information to Politkovskaya's murderers about her place of residence.
So far at least nine people have been arrested in connection with the case.
Investigators say they know who masterminded the hit, but the suspect’s name has not been revealed yet
Russian journalist and human rights activist Anna Politkovskaya was shot dead in her apartment building on October 7, 2006.