On June 22, 1941, Hitler’s men swept into Belarus and within a short period, killed some 800,000 of the Jews living there. Of those who remained, most left. A few stayed, but even now that number is dwindling. Riva Katz is one of four Jews in Ivenets, a shtetl wiped out by Nazis. She survived, as village children had been evacuated to Uzbekistan. June 22 marks the 70th anniversary of the Nazi invasion of Belarus.