Daniel Gaynor, 25, was targeted by a lone gunman while walking outside his home with his two kids and partner in Finglas on Saturday evening.
The lone killer walked up behind Gaynor and shot him three times, once in the neck. The gunman then fled by foot while Gaynor bled to death on the ground in front of his two children, aged six and seven.
Gaynor was taken to Connolly Hospital Blanchardstown, but was pronounced dead a short time later.
Gaynor’s father, Robert McGrath, was shot dead in Meath in 1992 after he pointed a sawn-off shotgun at gardaí during a post office robbery.
Gardaí are appealing for witnesses in what is believed to be the 15th gangland-linked killing this year.
Local Superintendent David Dowling said: “It was a bright sunny evening. We’re asking people to come forward to talk to us. It was a cold callous killing in front of his kids and his partner in broad daylight.”
Gaynor was shot at around 6.50pm beside a set of railings at the junction of Barnamore Crescent and Saint Helena’s Road in Finglas. The killer was seen fleeing towards the Tolka Valley Road.
The gunman was described as being between 5’9” and 6’ tall and wearing a light coloured top, a baseball cap and dark trousers.
Detectives later found a silver revolver nearby, thought to be the murder weapon.
Gaynor had a history of drugs and gun crimes since he was a teenager.
When 18, he fired a gun through the window of a house in Finglas to frighten the occupier into repaying him a €100 loan so he could buy his girlfriend a St Valentine’s Day present.
He also intimidated a witness in a separate trial against him by telling the mother that her son’s days were “numbered” before putting his fingers to his head in the shape of a gun.
On a separate occasion in court, Gaynor was also caught with cocaine on his possession during a hearing.
Up to 30 gardaí have been assigned to investigate the latest gangland killing.
Gaynor was a suspect in the shooting dead of Colm Owens last month, in which the father-of-one was gunned down while working at an animal feed store at a Finglas industrial estate.
Both Owens and Gaynor were associates of murdered drugs gang boss Eamon ‘The Don’ Dunne. Since the Finglas criminal leader was killed in a pub in April, attacks on associate gang members have taken place.
Earlier this month another man, who was a pallbearer at The Don’s funeral, was sprayed by gunfire in a pub but escaped with his life.