Georgi Markov began his career as a writer in his native Bulgaria. After defecting to the West in 1969, he continued his criticisms of the Bulgarian regime. On September 7, 1978, Markov was waiting at a London bus stop when he felt a sting on his leg and turned to see a man pick up an umbrella. Markov's death days later was attributed to the tiny, ricin-laced pellet that had been fired into his leg—likely from the umbrella. The "Umbrella Assassin" was never caught. Who is the prime suspect? Discuss (http://forum.thefreedictionary.com/postst66276_-Umbrella-Assassin--Strikes--1978-.aspx)