The man shot dead in north-west Dublin on Wednesday night had been involved in a prolonged feud with members of a criminal gang suspected of murdering his nephew last November, according to Garda sources.
Mr Gerard Fitzgerald, who was married with eight children, was himself shot and injured shortly before his nephew, Francis, was killed on November 16th last year.
According to local sources, Mr Fitzgerald (48), from Rathvilly Drive, Finglas south, was a well-known local criminal involved in robbery, drugs and extortion.
The killing of his nephew was part of a local feud between gangs trying to dominate criminal activity in the Finglas/Cabra area.
The feud has continued throughout this year and at least seven people have received gunshot injuries.
Mr Fitzgerald was standing at the at the junction of Oldtown Road and Shanliss Road in Finglas at 9.45 p.m. on Wednesday when a car pulled up and several shots were fired at him from a shotgun.
He was hit in the leg and at least twice in the body, it is understood.
His killers drove off in a stolen silver-coloured Rover car which was found burned out later at Ballystrane Lane near the meat-packing plant.
The previous attempt on his life was on November 6th last year. Mr Fitzgerald was shot twice in the legs and lower body when a gunman approached him as he pulled up outside his home in Rathvilly Drive.
It is understood Mr Fitzgerald, who had a considerable reputation for violence and was given the nickname "Concrete", retaliated against the criminals suspected of killing his nephew and that the dispute escalated in the past month.
His nephew was shot dead at a house in Annamoe Terrace, Cabra, after a row involving drugs, it is understood.
Francis Fitzgerald (26) was also regarded by garda∅ as being a career criminal and was reported to have been questioned about involvement in the robbery of £2.8 million in cash from the Brinks-Allied cash depot at Clonshaugh near Dublin airport, in January 1995.
The officer in charge of the investigation into Wednesday night's murder, Det Supt Joe McGarrity, has asked any witnesses to contact the incident room at Ballymun station, telephone (01) 666 4411.