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 Movement support the movement), Sham Shui Po, Kwai Shing East, Tai Wai, Tuen Mun, Chai Wan, Kwun Tong and other places. New campus of University of Macau, which is located on Zhuhai was hung with banner "Macau also need real universal suffrage" ["sic"], similar that of Hong Kong Umbrella Revolution, for echoing the street protests in the occupied territories of Hong Kong. Rallies in support of the protests occurred in over 64 cities worldwide by October 2014, principally in front of Hong Kong trade missions or Chinese consulates. A demonstration in front of the Chinese embassy in London attracted 3000 participants.