Vandals defaced a memorial to the victims of a Nazi forced labor camp, scratching swastikas into part of the structure, police said Monday. The vandalism at the Langenstein-Zwieberge site in eastern Germany, which was a subcamp of the Buchenwald concentration camp, occurred at some point between Thursday and Sunday, police said. In addition to the scratched swastikas, two information sheets were torn down. Langenstein-Zwieberge was established in 1944 to provide labor for building an underground aircraft factory nearby. The camp was liberated by American forces in 1945.