Censor.NET reports citing a law enforcement source.
According to available information, the attacker was dismissed in August 2016.
"The choice of the hitman by Russia's secret services was not accidental," the source said.
Denys Voronenkov was shot dead in downtown Kyiv March 23. The killer also managed to injure Voronenkov's bodyguard. The incident took place outside Kyiv's Premier Palace Hotel.
Voronenkov was a witness in the treason case against fugitive Ukrainian president Viktor Yanukovych. In his recent interview with Censor.NET Voronenkov said that Yanukovych was a traitor "who was involved in mass slaughter, who had fled to the foreign country and urged foreign troops to slay his people. I believe this person should have received not asylum but a fair trial in Russia."
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