Russia's Parliament has agreed a declaration blaming the Soviet dictator Joseph Stalin for personally ordering the Katyn massacre in which thousands of captured Polish officers were shot by Soviet forces during the Second World War. The mass executions were carried out by the Soviet secret police just months after the outbreak of the Second World War. For fifty years Soviet leaders blamed the Nazis for the massacre. It was only in 1990 Mikhail Gorbachev admitted Soviet forces had been responsible. But the investigation at that time did not go far and soon stopped its work. Human Rights Groups were outraged.