Less than two hours before he was fatally wounded, Detective Garda Colm Horkan shared banter with friends on What’s App about English Premier League soccer player, Declan Rice.
Lifelong friend and former Mayo senior footballer John Casey said somebody in their What’s App group had slagged off the West Ham footballer and Colm had posted his own comment “just for a bit of fun”.
“It’s hard to imagine that not long after he posted he was called to an incident where he was to lose his life," the Charlestown-based RTE pundit said.
“If you were to get into bother on the sporting field Colm would be the first to bail you out.”
He also described his friend as “solid as a rock, both on and off the field”.
He also told RTE Radio 1's News at One: "Colm was just one of those great friends and community men.
"Everybody liked him. I don't think he had an enemy. He got on with everybody. He was simply a role model in his professional and personal life."
Fighting back tears, John Casey’s mother, Angela, said all her children and the Horkan family grew up together and enjoyed a wonderful friendship.
“He had a great personality and was a beautiful dresser”, Mrs Casey recalled.
“Anytime we met on the street he would give me a big hug.
“My deepest sympathy to his dad, Marty, and the entire family.”
Charlestown Sarsfields GAA Club expressed condolences on its website.
"Colm and his family are synonymous with our club and Gaelic games within Mayo.
“A very dark cloud hangs over Fr O’Hara Park and our entire community today.”
Roscommon County Council Cathaoirleach Paschal Fitzmaurice said: “Castlerea is just in shock at what has happened.
“This sort of thing just does not happen around here. It is such a terrible thing to happen.
“This sort of thing just does not happen in Castlerea, let alone Roscommon.
"The last time it did was more than 40 years ago.”
Pharmacist Niamh Colleran described the killing as “an absolute tragedy”.
“Colm was such a gentleman, so mild and friendly,” she said.
“He contributed so much to the town and community during his short lifetime between playing football and fundraising.
"There was never a 10K race he wasn’t involved in.”
Publican John Finan described the young detective as “a fine-looking, well-mannered lad” who occasionally dropped in for a drink.
“I was stunned when my wife, Bridie, told me the awful news," he said.
A steady stream of sympathisers have been calling to the Horkan family home on the Kilkelly Road in Charlestown.
The callers included Charlestown parish priest, Fr Tommy Johnson.
He described the late Detective Garda as “an absolutely lovely guy, kind and gentle.
Fr Johnson said: “He gave generously of his time and talents for the good of others. Nobody could say a bad word about him."