During the 22nd century Dalek invasion, the Daleks discovered records which showed that Skaro had been destroyed during the Imperial-Renegade Dalek Civil War. The Seventh Doctor apparently had destroyed Skaro using the Hand of Omega. (PROSE: War of the Daleks) The destruction of Skaro occurred in the future, though the Doctor did not leave the 1963 time zone. See the Shoreditch Incident. After an unsuccessful attempt to change history, the Daleks realised that history could not be altered and Skaro would have to appear to be destroyed.