A mass grave containing 17.5 tonnes of human ashes has been unearthed in northern Poland, close to the former Nazi concentration camp of Soldau. Tomasz Jankowski from Poland's national remembrance institute said the grave contained at least 8,000 victims. The bodies are thought to have been dug up and burned in a Nazi operation to hide traces of their murders. The Nazis murdered Jews, political opponents and members of the Polish elite at Soldau. The concentration camp was built in 1939 for transit, internment and extermination and used throughout the Nazi occupation. Video: The treasure rewriting Danish history (BBC News)...