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
Waterloo, London Lambeth had significantly increased. After the opening of Waterloo railway station in 1848 via the Nine Elms to Waterloo Viaduct the locality around the station and Lower Marsh became known as Waterloo. The boundary of the ecclesiastical parish of St John Waterloo established in 1824 was formed by the River Thames in the north and west, approximated Westminster Bridge Road in the south, and followed the boundary with Southwark in the east. The public library in Waterloo was constructed in 1893. It remained open until the early 1960s when it was vacated due to its poor condition. The building now