On Nov. 21, 1974, 21 people were killed and 182 more were injured after concealed bombs were left off at two separate pubs in the city of Birmingham, England. For 30 years, the British territory of Northern Ireland was consumed by sectarian violence known as “The Troubles”. In 2014, a senior officer of the Irish Republican army, one of the main factions in “The Troubles”, confessed to his role in the Birmingham bombings. He said the bombers hadn't intended to kill any civilians, but they were unable to phone the police in time to have the locations of the concealed bombs cleared after they were dropped off.