The Jews of Kyiv are first mentioned in a 10th century letter, but the Jewish population remained relatively small until the nineteenth century. A series of pogroms was carried out in 1882, and another in 1905. On the eve of World War I, the city's Jewish population was over 81,000, and by 1939 there were approximately 224,000 Jews in Kyiv, some of whom fled the city ahead of the German invasion of the Soviet Union that began in June 1941. On 29 and 30 September 1941, nearly 34,000 Kyivan Jews were massacred at Babi Yar by the German Wehrmacht, SS, Ukrainian Auxiliary Police, and local collaborators. Jews began returning to Kyiv at the end of the war, but experienced another pogrom in September 1945. In the 21st century, Kyiv's Jewish community numbers about 20,000. There are two major synagogues in the city: the Great Choral Synagogue and the Brodsky Choral Synagogue.