Garda Commissioner Martin Callinan said the entire force had been deeply shocked and saddened by the murder of Detective Garda Adrian Donohoe - the first of a serving officer in 17 years.
Commissioner Callinan said: "He was a very popular member of An Garda Siochana, a very efficient member, someone who was revered both by his peers and members of the community where he served."
A wide police cordon extending for several miles was still in place around the crime scene outside Lordship Credit Union at Bellurgan, Jenkinstown which is about seven miles outside Dundalk.
Specialist officers from the Garda Forensic and Technical Bureau were combing the area for clues and could be seen scouring the bushes and hedgerows lining the rural roads. A blue tent was erected in the Credit Union carpark where the officer was tragically cut down.
The slain officer's body was taken away last night to Our Lady of Lourdes Hospital in Dundalk where a post mortem examination was expected to be carried out.
Taoiseach Enda Kenny has said the murder of Detective Garda Adrian Donohoe, who was shot dead in Ireland last night in a botched hold-up was an "outrageous and appalling act of cold blooded violence". He said:
(It) has left a family without a husband and father and the Garda Siochana without a brave and valued member.
On behalf of the Government and of the people I would like to express my condolences to Adrian's wife and children and to all his extended family at this unbearably sad time.
A detective gunned down during a botched bank heist in Ireland was killed less than half a mile from his home.
Detective garda Adrian Donohoe, a father of three in his 40s, died as he tried to prevent raiders escaping with cash from Lordship Credit Union at Bellurgan, Jenkinstown about seven miles from the border town of Dundalk, Co Louth.