However , as the Provisional IRA campaign 1969 – 1997 grew in ferocity in the early 1970s , the Army was increasingly caught in a situation where its actions were directed against the IRA and the Catholic Irish nationalist community which harboured it . In the early period of the conflict , British troops mounted several major field operations . The first of these was the Falls Curfew of 1971 , when over 3,000 troops imposed a 3-day curfew on the Falls Road area of Belfast and fought a sustained gun battle with local IRA men . In Operation Demetrius in June 1971 , 300 paramilitary suspects were interned without trial , an action which provoked a major upsurge in violence . The largest single British operation of the period was Operation Motorman in 1972 , when about 21,000 troops were used to restore state control over areas of Belfast and Derry , which were then controlled by republican paramilitaries . The British Army 's reputation suffered further from an incident in Derry on 30 January 1972 , Bloody Sunday in which 13 Catholic civilians were murdered by The Parachute Regiment . The biggest single loss of life for British troops in the conflict came at Narrow Water , where eighteen British soldiers were killed in a PIRA bomb attack on 27 August 1979 , on the same day Lord Mountbatten of Burma was assassinated by the PIRA in a separate attack . In all almost 500 British troops died in Northern Ireland between 1969 and 1997 . Most of these deaths however occurred in the early 1970s , when British troops were placed at the forefront of the conflict and had little experience in dealing with a low intensity conflict in a predominantly urban , heavily populated area
Bloody Sunday
Bloody Sunday (1972)
History of the British Army