Sean O'Callaghan

Sean O'Callaghan (born 26 January 1954) is a former member of the Provisional Irish Republican Army (IRA). Between 1979 and 1988 he worked against the organization from within as an intelligence agent for the Irish Government with the Garda Síochána's Special Branch. In 1988 he left the IRA and voluntarily surrendered to British prosecution. Following his release from imprisonment he published a memoir detailing his life in Irish paramilitarism entitled The Informer: The True Life Story of One Man's War on Terrorism.

O'Callaghan was born on 26 January 1954, into a family with a Fenian paramilitary history, in Tralee, County Kerry. His paternal grandfather had taken the Anti-Treaty side during the Irish Civil War, and his father had been interned by the Irish Government during at the Curragh Camp in County Kildare for I.R.A. activity during World War 2..

By the late 1960s the teenaged O'Callaghan had ceased practising the Catholic religion, and adopted Atheism and had become interested in the theories of Marxist revolutionary politics, which found an outlet of practical expression in the sectarian social unrest in Ulster at that time, centered on the activities of the Northern Ireland Civil Rights Association. In 1969 an outbreak of communal violence broke out in Ulster, and believing that British imperialism was responsible O'Callaghan joined the newly founded Provisional IRA at the age of 16. Soon afterwards, he was arrested by local Gardaí after he accidentally detonated a small amount of explosives, which caused damage to his parents' house and those of his neighbours. After demanding, and receiving, treatment as a political prisoner, O'Callaghan quietly served his sentence.

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