Adrian Donohoe
Garda detective Adrian Donohoe, who was shot dead in the armed robbery

Irish police have launched a hunt for four men they believe responsible for the murder of a detective during an armed robbery in County Louth.

Garda detective Adrian Donohoe was shot dead in a botched hold-up at a credit union in Dundalk, close to the border with Northern Ireland, late on Friday 25 January.

The four men were seen outside the Lordship Credit Union at Bellurgan, Jenkinstown - about seven miles outside Dundalk town - as staff locked up at the end of their shift.

The detective approached the men and shots were fired before the suspects fled in a grey Volkswagen Passat, according to reports. The suspects are believed to have escaped with money, Garda sources say.

Detective Donohoe, who was in his late thirties and married with three children, was on escort duty with another detective when the incident occurred.

He was pronounced dead shortly afterwards, while his colleague was unharmed. Forensic officers sealed off the scene and a helicopter was deployed to assist in the search.

Armed patrols were despatched across the region and the Police Service of Northern Ireland called in for assistance, amid fears the gang may have escaped across the border.

Irish President Michael D Higgins described the killing as "a dreadful crime" that would "truly appal" the country.

Sinn Fein president and County Louth representative Gerry Adams said he was deeply shocked by the detective's murder. "I extend my deepest sympathies to his family and colleagues, and appeal to those with information about this crime to co-operate with the Gardai," Adams said.

Sinn Fein councillor Jim Loughran described the victim, who lived half a mile from the murder scene, as "a quiet, decent family man" who was involved in coaching players at the local sports club, St Patrick's.

"I can't believe this has happened," said Loughran. "I just spoke to him last week on the street in town. This was not just an attack on a Garda detective, it was an attack on the whole community."

Irish justice minister Alan Shatter said: "The Irish people will share my revulsion and horror that a Garda has so tragically lost his life in the course of his duties."

Councillor Declan Breathnach said the shop "would be fairly busy on a Friday evening, with some people just getting their week's pay or wanting to sort out money for the weekend". He added: "This was just such a despicable, heinous act. I still can't believe it but I utterly condemn it."

Garda officers have appealed for witnesses to contact them at Dundalk Garda station.