November 21st 1920 Bloody Sunday In Dublin
By late 1920, Michael Collin's squad had been very successful in taking out the G division of Dublin Castle.
In response to this, the British set up a new spy network of intelligence officers most of whom had served in Egypt & Palestine during WW1, so they became known as the 'Cairo Gang'.
Fearing the Cairo gang was close to assassinating leading Republican figures in Dublin, the IRA decided to strike first.
Through informers within the crown forces and sympathetic ears placed in the right places, the IRA became aware of the addresses of the Cairo Gang.
At first, fifty names were on the list but this was reduced to thirty-five then to twenty agents in eight locations. On the morning of Sunday, November 21st 1920, the squad helped by members of the Dublin brigade mounted their operation.
In total, 15 of the targets were killed with many others not being at known locations. Although a high number of the targets were not caught, the events that morning had the majority of them running scared, with many fleeing Dublin Castle.
Later that afternoon Dublin were playing Tipperary in a Gaelic football match in Croke Park, during the match the RIC fired on the crowd killing fourteen innocent people including the Tipperary goalkeeper Michael Hogan, many others were wounded by the shooting and by a stampede while trying to escape.
The British claimed they were fired on first but a British military investigation which was held shortly after the massacre but only released in the year 2000 found that “the fire of the RIC was carried out without orders and exceeded the demands of the situation” and Major-General Boyd, the officer commanding Dublin District, added “the firing on the crowd was carried out without orders, was indiscriminate, and unjustifiable, with the exception of any shooting which took place inside the enclosure”.
That evening three Republicans Dick McGee, Peadar Clancy & Conor Clune who were been held in Dublin Castle were tortured and shot dead by tier captures who tried to stage an attempted escape as justification for their killings.
A combination of the loss of the Cairo Gang, which devastated British Intelligence in Ireland, and the public relations disaster that was Bloody Sunday severely damaged the cause of British rule in Ireland and increased support for the republican government under Éamon de Valera.
The events of Bloody Sunday have survived in public memory. The Gaelic Athletic Association named one of the stands in Croke Park the 'Hogan Stand' in memory of Michael Hogan, the football player killed in the incident.