Thousands of survivors of three Nazi concentration camps have attended ceremonies in Germany to mark the 60th anniversary of their liberation. Former prisoners of Ravensbrück, Bergen-Belsen and Sachsenhausen were joined at the camps by world leaders and former servicemen. Some wore the blue-and-white striped scarves, recalling the camps' uniform. Tens of thousands of people died in the camps from hunger, disease, exhaustion or medical experiments. Some 300 survivors gathered at Ravensbrück, north of Berlin, at the site of a former Nazi camp for women prisoners. Around 132,000 women and children, 20,000 men and 1,000 female youths were held there, and many of them died from hunger, disease, exhaustion or medical experiments. At the nearby Sachsenhausen camp, people threw roses into a pond used by the Nazis to dump the ashes of the camp's victims after they had been cremated. Survivors of Bergen-Belsen, near Hanover, held private ceremonies on Friday to mark their liberation by British troops on 15 April 1945. A further ceremony was also held on Sunday at the camp, whose victims included Anne Frank, who died of typhus a few weeks before the camp was liberated, leaving behind her now famous diary.