GARDA Tony Golden is the 88th member of An Garda Síochana to be killed in the line of duty since the foundation of the force.
Garda Commissioner Noirín O'Sullilan said the thoughts of the entire force were with the bereaved families of all 88 Gardaí who have died since 1922.
"It brings for us into very sharp focus the dangers faced by the men and women of An Garda Síochana every single day in going about their duty, in protecting the community, and in protecting vulnerable members of the community," she said.
Prior to Sunday night, the last garda to lose his life was Mr Golden’s divisional colleague Adrian Donohoe (41), shot dead as he approached a criminal gang outside Lordship Credit Union, near Dundalk, in January 2013.
Investigating gardaí have taken hundreds of statements and have tracked suspects to Northern Ireland as well as to the US and Australia, but no-one has yet been charged with the murder.
The first garda to die on duty was Henry Phelan, who was shot dead in Co Kilkenny in November 1922 when the force was still referred to as the Civic Guard.
However, the Troubles have resulted in some of the most high-profile garda killings.
The first garda victim was Richard Fallon (43), who was shot dead on April 3 1970 while pursuing raiders at the then Royal Bank, now AIB, in Dublin.
He was the first garda to be murdered in almost 30 years and his death sent shockwaves throughout the Republic.
The Fallon family continues to seek a full public inquiry into the officer’s killing amid claims that the then Fianna Fáil government assisted members of the Saor Eire gang to escape after the murder.
In 1975, unarmed Garda Michael Reynolds (30) suffered a fatal gunshot wound to the head after he chased two bank robbers in the Raheny area of Dublin. The death sentence imposed on two raiders would eventually be commuted to life imprisonment.
Five years later Detective John Morley (38) and Garda Henry Byrne (30) were shot dead while pursuing three masked members of a republican gang who had robbed a Bank of Ireland branch in Ballaghadreen, Co Roscommon.
Sergeant Patrick Morrisey (49) was gunned down in June 1985 as he chased two men who had robbed a Labour Exchange in Dundalk, Co Louth. The raiders opened fire on the unarmed Sergeant Morrissey after their car was involved in an accident.
Perhaps the garda killing that has received the greatest level of international attention was that of Detective Jerry McCabe, shot dead in June 1996 by a Provisional IRA gang in the Co Limerick village of Adare.
The gang, who had been attempting to rob a postal van, opened fire with an AK-47 on Detective McCabe and his colleague Detective Ben O’Sullivan as they sat in their car, hitting both multiple times. The attack took place just weeks after the breakdown of the first PIRA ceasefire.
After a massive manhunt that led to numerous arrests, Pearse McAuley, originally from Strabane in Co Tyrone, and Limerick man Kevin Walsh (52), were sentenced to 14 years imprisonment for the detective’s manslaughter while three others received shorter sentences.
Detective McCabe’s widow Ann McCabe conducted a long-running campaign, lobbying successive Dublin governments, to ensure her husband’s killers served their full prison terms and did not gain early release under the terms of the 1998 Good Friday Agreement.
