Russian President Vladimir Putin on Friday repeated a claim that neo-Nazis were committing crimes in Ukraine -- an allegation Moscow has used to justify its military intervention -- as the world marked Holocaust Remembrance Day. "Forgetting the lessons of history leads to the repetition of terrible tragedies," Putin said. "This is evidenced by the crimes against civilians, ethnic cleansing and punitive actions organised by neo-Nazis in Ukraine. It is against that evil that our soldiers are bravely fighting," he said in a statement.