IRA members went to Motion a number of addresses Expressing_publicly and killed Killing or fatally wounded Bodily_harm fifteen people : nine British Army officers , a Royal Irish Constabulary ( RIC ) officer , two members of the Auxiliary Division , two civilians , and another man who is believed to have been an intelligence agent .

Later that afternoon , members of the Auxiliary Division and RIC opened Action fire on the crowd at a Gaelic football match Competition in Croke Park , killing Killing or fatally wounding Bodily_harm fourteen civilians and wounding Bodily_harm at least sixty others .

The Irish War Hostile_encounter of Independence ( ) or Anglo-Irish War Hostile_encounter was a guerrilla war Hostile_encounter fought Hostile_encounter in Ireland from 1919 to 1921 between the Irish Republican Army ( IRA , the army of the Irish Republic ) and British forces Military_operation : the British Army , along with the quasi-military Royal Irish Constabulary ( RIC ) and its paramilitary forces Military_operation the Auxiliaries and Ulster Special Constabulary ( USC ) .

That day , two RIC officers were shot Use_firearm dead Death in the Soloheadbeg ambush Attack by IRA volunteers acting on their own initiative Participation .

The IRA began Process_start ambushing Attack RIC and British Army patrols Patrolling , attacking Attack their barracks and forcing isolated barracks to be abandoned GiveUp .

The British government bolstered Cause_change_of_strength the RIC with recruits from Britain—the Black and Tans and Auxiliaries—who became Becoming notorious for ill-discipline and reprisal attacks Attack on civilians , some of which were authorised Preventing_or_letting by the British government .

On Bloody Sunday in Dublin , 21 November 1920 , fourteen British intelligence operatives were assassinated Killing in the morning ; then in the afternoon the RIC opened Openness fire on a crowd at a Gaelic football match Competition , killing Killing fourteen civilians and wounding Bodily_harm 65 .