Ukrainian and Israeli leaders took part in a ceremony to mark the 70th anniversary of the Nazi massacre of Jews at Babi Yar ravine in Kiev on Monday. Ukrainian President Viktor Yanukovych, Prime Minister Mykola Azarov, Parliament Speaker Volodymyr Lytvyn and Deputy Prime Minister and Foreign Minister of Israel Avigdor Lieberman laid flowers to the foot of a giant monument at the National Historical and Memorial Preserve \"Babi Yar\" to commemorate tens of thousands of Jewish victims. A series of commemoration activities began in Ukraine on Sept. 29. Seventy years ago, a terrible tragedy occurred in Kiev, when Nazi occupiers murdered at least 33,771 Jewish citizens during a two-day massacre. In the following years, Nazi executed more than 100,000 people at Babi Yar, including thousands of Soviet prisoners.