Ivan Safronov had been investigating arms deals shortly before he was found dead in front of his home in March.
"No crime was uncovered in this case. In the course of the investigation the 'criminal version' was fully investigated. No evidence of that was discovered," an unidentified official from the Prosecutor-General's Office told Interfax.
He added, however, that the investigation was not yet finished.
Ilya Bulavinov, the deputy editor of the "Kommersant" daily that employed Safronov, told the Reuters news agency that the official investigation was not thorough enough.
Russia ranks as one of the world's deadliest countries for journalists.
The Erosion Of CIS Press Freedom
FROM BAD TO WORSE. RFE/RL and Freedom House experts held a panel discussion at which they analyzed the erosion of press freedom in many CIS countries. According to Freedom House rankings, in 1994, six of the 12 CIS countries were rated "partly free"; by 2004, 11 of the 12 were rated "not free."
LISTENListen to the entire briefing (about 70 minutes):
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