WARSAW, POLAND—BBC News reports that a mass grave containing more than 17 tons of ashes has been found in northern Poland, near the site of Soldau, a Nazi concentration camp where as many as 30,000 Jews, political opponents of the Nazis, and members of the Polish intelligentsia and clergy were killed. The ashes are thought to represent at least 8,000 bodies that had been exhumed and burned in a Nazi effort to destroy evidence of the murders. To read about remote sensing of another Nazi killing site, go to "World Roundup: Lithuania."