Ricin immunogenic in mice, rabbits, and humans. It has completed two successful clinical trials. Ricin has been involved in a number of incidents. In 1978, the Bulgarian dissident Georgi Markov was assassinated by Bulgarian secret police who surreptitiously shot him on a London street with a modified umbrella using compressed gas to fire a tiny pellet contaminated with ricin into his leg. He died in a hospital a few days later and his body was passed to a special poison branch of the British Ministry of Defence (MOD) that discovered the pellet during an autopsy. The prime suspects were the Bulgarian
Umbrella man (JFK assassination) with a paralyzing agent at Kennedy to immobilize his muscles and make him a "sitting duck" for an assassination. After an appeal to the public by the United States House Select Committee on Assassinations (HSCA), Louie Steven Witt came forward in 1978 and claimed to be the "umbrella man". He claimed still to have the umbrella and did not know he had been the subject of controversy. He said that he brought the umbrella simply to heckle Kennedy whose father Joseph had been a supporter of the Nazi-appeasing British Prime Minister Neville Chamberlain. By waving a black umbrella, Chamberlain's trademark