An investigation into the suicide of a retired Irish police officer who shot himself with an Uzi sub-machine gun will focus on how the former detective was able to access firearms in a garda station.

Det Peter O'Donnell, who retired three weeks ago, walked into Carrick-on-Shannon garda station on Saturday morning, got access to an armoury and took his own life.

Yesterday, prayers were said for him at masses in Carrick-on-Shannon and in his native Ardara in Co Donegal where many of his large family live.

Two investigations were immediately launched following the death, one by the Garda Siochana Ombudsman Commission (GSOC) and another by the gardai.

Det O'Donnell, who had been in the force for 35 years, had developed a habit since his retirement of calling on his former colleagues in Carrick-on-Shannon for a chat and a cup of coffee after he collected the morning paper.

On Saturday, when he said he needed to finish work on a file, he was given access to the district detective office. From there he passed into a small armoury room, unlocked a steel weapons safe, and shot himself with the Uzi sub-machinegun.

It is understood that the investigation into his death will centre around how he got access to the weapons cabinet as he was a retired officer.

Last night, a spokesman for the GSOC said a team had arrived in the station a few hours after the incident and a full examination of the scene had taken place. The investigation is on-going, he said.

A post mortem examination was carried out yesterday by Irish state pathologist Dr Marie Cassidy in Sligo General Hospital prior to the removal of his remains to his home at Summerhill, Carrick-on-Shannon, Co. Leitrim.

Det O'Donnell was married to his wife Mary and had four children, who are aged from their late teens to early 20s. He was well known for his involvement in the local community, notably in athletics and the Community Games.

The community in Ardara were said to be numbed with grief at the death.

“It is many years since Peter left Ardara but he was a frequent visitor back to the area. He loved this town and Donegal GAA. The entire community is shocked,” said a former school-friend.

Det O'Donnell joined the force in March 1974. He served for three years in Galway and was then posted to Dowra, Co Cavan, and Monaghan before a 1980 transfer to Carrick-on-Shannon where he served the remaining 29 years.

A spokesman for the garda press office said they had no comment to make on the matter.