Bulgaria–United States relations to work. Bulgaria became a member of the Warsaw Pact on May 14, 1955. Though no Soviet troops were stationed on Bulgarian soil, in 1968, Zhivkov sent a Bulgarian division to join Polish, Hungarian and Soviet troops to crush a popular uprising in Prague. In 1978, the Bulgarian secret police were implicated in the assassination in London of Georgi Markov, a Bulgarian dissident who was a correspondent for the BBC World Service, Deutsche Welle radio and the U.S. sponsored Radio Free Europe. Markov was assassinated with a poisoned umbrella on September 7, Zhivkov's birthday. The rise of democratic movements across
Umbrella man (JFK assassination) Umbrella man (JFK assassination) The "umbrella man", identified by the United States House Select Committee on Assassinations in 1978 as Louie Steven Witt, is a name given to a figure who appears in the Zapruder film, and several other films and photographs, near the Stemmons Freeway sign within Dealey Plaza during the assassination of John F. Kennedy. Witt is the subject of a 2011 documentary short, "The Umbrella Man", by Errol Morris for "The New York Times". A person popularly dubbed the "umbrella man" has been the object of much speculation, as he was the only person seen carrying, and