In January 1972, an incident occurred during a Northern Ireland Civil Rights Association march in Derry, during which paratroopers shot and killed thirteen unarmed civilians. A fourteenth civilian was to die later. What history has come to know as Bloody Sunday was, in essence, the end of Faulkner's government. In March 1972, Faulkner refused to maintain a government without security powers which the British government under Edward Heath decided to take back. The Stormont parliament was subsequently prorogued (initially for a period of one year) and following the appointment of a Secretary of State for Northern Ireland, William Whitelaw, direct rule was introduced.