Investigators suspect Politkovskaya was killed over articles criticizing Kremlin policies in the North Caucasus and the leadership in Chechnya, RIA Novosti reported Tuesday.
Lom-Ali Gaitukayev of Chechnya is accused of hiring three of his relatives and a former police official to shoot Politkovskaya to death in the elevator of her apartment building in October 2006.
Gaitukayev was reportedly paid $150,000 by an unidentified person to make the arrangements.
Politkovskaya's colleagues and relatives have repeatedly urged investigators to identify the mastermind behind the crime.
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