Austrian President Heinz Fischer (3rd R), Chancellor Werner Faymann (4th L) and President of the Austrian National Assembly Barbara Prammer (3rd L) pay tributes to those killed during the ceremony to mark the 67th anniversary of Mauthausen Concentration Camp's liberation in Upper Austria, May 13, 2012. The Mauthausen Concentration Camp was the first of its kind established in a foreign country by Nazi Germany. It was one of the most notorious camps in the Nazi concentration camp system. [Xinhua]