Italians destroyed 2,000 churches and 525,000 houses, while confiscating or slaughtering 6 million cattle, 7 million sheep and goats, and 1.7 million horses, mules, and camels, leading to the latter deaths. During the 1936–1941 Italian occupation, atrocities also occurred; in the February 1937 Yekatit 12 massacres as many as 30,000 Ethiopians may have been killed and many more imprisoned as a reprisal for the attempted assassination of Viceroy Rodolfo Graziani. A 2017 study estimated that 19,200 were killed - a fifth of the population of Addis Ababa. The Ethiopian Orthodox Tewahedo Church was especially singled out. Thousands of Ethiopians also died in concentration camps such as Danane and Nocra. Spanish Civil War 75,000 Italian soldiers of the Corpo Truppe Volontarie fought on the side of the Nationalists during the Spanish Civil War, as did 7,000 men of the Aviazione Legionaria. While they also bombed valid military targets such as the railway infrastructure of Xativa, the Italian air force partook in many bombings of civilian targets for the purposes of "weakening the morale of the Reds". One of the more notable bombings was the Bombing of Barcelona, in which 1,300 civilians were killed, with thousands more being wounded or dehoused. Other cities subjected to terror bombing by the Italians included Durango, Alicante, Granollers, and Guernica. Documents found in British archives by the historian Effie Pedaliu and documents found in Italian archives by the Italian historian Davide Conti, pointed out that the memory of the existence of the Italian concentration camps and Italian war crimes committed during the Spanish Civil War had been repressed due to the Cold War. World War II The British and American governments, fearful of the post-war Italian Communist Party, effectively undermined the quest for justice by tolerating the efforts made by Italy's top authorities to prevent any of the alleged Italian war criminals from being extradited and taken to court. Fillipo Focardi, a historian at Rome's German Historical Institute, has discovered archived documents showing how Italian civil servants were told to avoid extraditions. A typical instruction was issued by the Italian prime minister, Alcide De Gasperi, reading: "Try to gain time, avoid answering requests." The denial of Italian war crimes was backed up by the Italian state, academe, and media, re-inventing Italy as only a victim of the German Nazism and the post-war Foibe massacres. A number of suspects, known to be on the list of Italian