The Russian Archives have posted documents which shed light on the Soviet Union’s World War II massacre of more than 20,000 Polish officers and other prominent citizens. The Soviet Union had blamed the massacres on Nazi forces who invaded in 1941. This explanation had remained the official state position until Soviet leader Mikhail Gorbachev acknowledged Soviet responsibility in 1990. The current Russian President, Dmitry Medvedev, has promised that more similar documents would also be released. The documents are available on the following site:
http://rusarchives.ru/publication/katyn/spisok.shtml (In Russian)
Also see: Excerpts: Beria letter to Stalin on Katyn (From BBC news in English)
Reconciliation of European Histories 