Investigators have interviewed more than 600 people as part of investigations into the murder of rights activist Natalya Estemirova, Russia's special investigations committee said on Friday.
Estemirova, who had been investigating kidnappings and disappearances in Chechnya for the Russian human rights group Memorial, was abducted outside her home in the Chechen capital of Grozny on July 15, 2009. She was found shot dead in the neighboring North Caucasian republic of Ingushetia later the same day.
Committee spokesman Vladimir Markin said that over 100 people from Estemirova's inner circle had been questioned, including at least 40 Memorial members, foreign journalists, family members and friends.
"All the information received from rights activists has been verified and included in the case file," he said.
Markin said investigators were "ready to consider and check any additional information pertinent to the case."
Russian President Dmitry Medvedev said on Thursday that those who had ordered Estemirova's murder would be found.
He said the identity of her assassin had been established but not publicly disclosed.
EU High Representative Catherine Ashton called on Thursday for a swift conclusion to the investigation and urged Russian authorities "to work towards putting an end to the climate of impunity and fear in the North Caucasus."
MOSCOW, July 16 (RIA Novosti)
