Poland ' s Institute of National Remembrance(IPN) says it has found a mass grave containing the bodies of about 83 people thought to have been victims of a Stalin - era campaign of terror.IPN said on Friday that the grave was uncovered at the edge of Powazki military cemetery in the Polish capital Warsaw. The bodies are believed to be victims of the post-war Stalinist reign of terror against Polish anti-Nazi and anti-Soviet partisans during the 1940s and 1950s. IPN's forensic specialists said the remains belong to the victims killed by a bullet to the neck and that they would use DNA testing to ascertain their identities. The institute says nearly 50,000 people were killed during the reign of terror in Poland and many of the surviving family members still trying to locate their places of burial. As part of a research project launched in 2011, digs are underway across the country to identify the victims of Stalinism.