When I was working on the story of the attempted poisoning of former Colonel GRU Sergey Skripal in the English city of Salisbury, I managed to find a witness who confirmed that Russian special services have long been interested in deadly poisons.  Felix Kubin used to do some assignments for a certain Bashir Kushtov, whom he calls a high-ranking strongman, and who carried out orders from then Russian Minister of Internal Affairs Rashid Nurgaliyev, but also had connections to the FSB.

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