 After the invasion of Poland in September 1939, the secret Aktion T4 euthanasia programme – the systematic murder of German, Austrian and Polish hospital patients with mental or physical disabilities – was initiated by the "SS" in order to eliminate "life unworthy of life" (), a Nazi designation for people who had no right to life.In 1941, the experience gained in the secretive killing of these hospital patients led to the creation of extermination camps for the implementation of the Final Solution.By then, the Jews were already confined to new ghettos and interned in Nazi concentration camps along with other targeted groups, including Roma, and the Soviet POWs.