The arrest of former top Moscow police officer Dmitry Pavlyuchenkov could be a major breakthrough in the murder case of Anna Politkovskaya, one of the Kremlin's most vocal critics.
Anna Politkovskaya was murdered three years ago, but her killers have not been brought to justice. Russian journalists say that's a sign of how dangerous their jobs have become.
Sergei Protazanov's killing in March was the latest in a series of violent attacks targeting journalists.
Human rights advocates charge that the trial was shoddy and followed a weak investigation.