In February 1945, Prague suffered several bombing raids by the US Army Air Forces. 701 people were killed, more than 1,000 people were injured and some buildings, factories and historical landmarks (Emmaus Monastery, Faust House, Vinohrady Synagogue) were destroyed. Many historic structures in Prague, however, escaped the destruction of the war and the damage was small compared to the total destruction of many other cities in that time. According to American pilots, it was the result of a navigational mistake. In March, a deliberate raid targeted military factories in Prague, killing about 370 people. On 5 May 1945, two days before Germany capitulated, an uprising against Germany occurred. Several thousand Czechs were killed in four days of bloody street fighting, with many atrocities committed by both sides. At daybreak on 9 May, the of the Red Army took the city almost unopposed. The majority (about 50,000 people) of the German population of Prague either fled or were expelled by the Beneš decrees in the aftermath of the war. Cold War Prague was a city in a country under the military, economic, and political control of the Soviet Union (see Iron Curtain and COMECON). The world's largest Stalin Monument was unveiled on Letná hill in 1955 and destroyed in 1962. The 4th Czechoslovak Writers' Congress, held in the city in June 1967, took a strong position against the regime. On 31 October 1967 students demonstrated at Strahov. This spurred the new secretary of the Czechoslovak Communist Party, Alexander Dubček, to proclaim a new deal in his city's and country's life, starting the short-lived season of the "socialism with a human face". It was the Prague Spring, which aimed at the renovation of political institutions in a democratic way. The other Warsaw Pact member countries, except Romania and Albania, were led by the Soviet Union to repress these reforms through the invasion of Czechoslovakia and the capital, Prague, on 21 August 1968. The invasion, chiefly by infantry and tanks, effectively suppressed any further attempts at reform. The military occupation of Czechoslovakia by the Red Army would end only in 1991. Jan Palach and Jan Zajíc committed suicide by self-immolation in January and February 1969 to protest against the "normalization" of the country. After the Velvet Revolution In 1989, after riot police beat back a peaceful student demonstration, the Velvet Revolution crowded the streets of Prague, and the capital of Czechoslovakia benefited greatly