During the 1970s , the Glenanne gang — a secret alliance of loyalist militants , British soldiers and RUC officers — carried out a string of attacks against Catholics in an area of Northern Ireland known as the " murder triangle " . It also carried out some attacks in the Republic . '' Lethal Allies : British Collusion in Ireland '' claims the group killed about 120 people , almost all of whom were reportedly uninvolved Catholic civilians . The '' Cassel Report '' investigated 76 murders attributed to the group and found evidence that soldiers and policemen were involved in 74 of those . One member , RUC officer John Weir , claimed his superiors knew of the collusion but allowed it to continue . The '' Cassel Report '' also said some senior officers knew of the crimes but did nothing to prevent , investigate or punish . Attacks attributed to the group include the Dublin and Monaghan bombings ( 1974 ) , the Miami Showband killings ( 1975 ) and the Reavey and O'Dowd killings ( 1976 )
Reavey and O'Dowd killings
Reavey and O'Dowd killings
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