Ricin the attack on Georgi Markov another Bulgarian defector, Vladimir Kostov, survived a similar attack. Kostov was standing on an escalator of the Paris metro when he felt a sting in his lower back above the belt of his trousers. He developed a fever, but recovered. After Markov's death the wound on Kostov's back was examined and a ricin-laced pellet identical to the one used against Markov was removed. Several terrorists and terrorist groups have experimented with ricin and caused several incidents of the poisons being mailed to U.S. politicians. For example, on May 29, 2013 two anonymous letters sent to
Assassination assassinated by ricin poisoning. A tiny pellet containing the poison was injected into his leg through a specially designed umbrella. Widespread allegations involving the Bulgarian government and KGB have not led to any legal results. However, after the fall of the USSR, it was learned that the KGB had developed an umbrella that could inject ricin pellets into a victim, and two former KGB agents who defected said the agency assisted in the murder. The CIA made several attempts to assassinate Fidel Castro, many of the schemes involving poisoning his cigars. In the late 1950s, KGB assassin Bohdan Stashynsky killed