Detective Colm Horkan has been described as a 'role model' and someone 'you would bring into the trenches with you' by a close friend.
Ex-Mayo footballer John Casey has paid an emotional tribute to the garda after he was shot dead in Roscommon overnight.
The pair grew up together in Charlestown, Co Mayo, and Casey has described the local community as 'numb' after the tragic shooting.
"The community are beyond devastated. The town is numb with pain at the moment," Casey said.
"Colm was a great GAA man. He won a County Minor title in 1988, County Under-21 title in 1991, and County Intermediate in 1993. He was a GAA fanatic and when you are a GAA fanatic in a GAA community you blend in very well.
"He was respected by everyone who knew him. Always turned out very well, always looked pristine.
"Colm is the fellow you would bring into the trenches with you.
"I remember I was a couple of years his junior and several times I got into trouble on the football pitch and just before I was to get put in my place, lo and behold Colm was there to lend a hand and offer assistance.
"He was the guy you would pick to be on your team first every time because you'd know he wouldn't see you stuck.
"He loved his job. He was a mad Liverpool fan, mad Mayo fanatic. He's the type of guy, even myself as a former county player, you would just respect what advice Colm Horkan had to give you about football.
"He would have been your role model guard. He was straight as a die. What you saw with Colm was what you'd get.
"Ultimately it cost him his life."
Garda Commissioner Drew Harris has said there is no signs at this moment that the shooting of Garda Colm Horkan is part of wider organised crime.
Speaking to media in Castlerea, Co Roscommon, Mr Harris said: “What we have here is a random act. A violent act that has led to the death of Detective Garda Horkan.
“So it is tragic and it is an attack upon us all. Policing is an extension of good citizenship and we should acknowledge that this demeans and grieves us all as a society.”
Mr Harris added that Det Horkan was on a general anti-crime patrol at the time of the attack.
He added that it is difficult to say whether or not the suspect was known to Det Horkan given that he would have known many people in the local area due to his work.
A murder investigation has been launched after a garda detective was shot dead in Co Roscommon.
Detective Garda Colm Horkan, who had served with the Garda for 24 years, was killed in an incident in the town of Castlerea just before midnight.
A man in his 40s has been been arrested and is being held at Castlerea Garda Station.
