The "Manchester Martyrs" is a term used to refer to William Philip Allen, Michael Larkin, and Michael O'Brien who were executed for the murder of a police officer in Manchester, England, in 1867, during an incident that became known at the time as the "Manchester Outrages". The three were members of the Irish Republican Brotherhood, also known as the Fenians, an organisation dedicated to ending British rule in Ireland, and were among a group of 30–40 Fenians who attacked a horse-drawn police van transporting two arrested leaders of the Brotherhood, Thomas J. Kelly and Timothy Deasy, to Belle Vue Gaol. Police Sergeant Charles Brett, travelling inside with the keys, was shot and killed as the attackers attempted to force the van open by blowing the lock. Kelly and Deasy were released after a