MR TIM Rattigan (49) died yesterday afternoon after being on a lifesupport machine since he was shot in the head on Saturday. He was a smalltime criminal who gardai say had not come to their attention in recent years.
His convictions were for minor offences and he was not regarded as a significant presence in the criminal world.
"He seems to have got caught up in an ongoing row with some people and he got the brunt of it," one source said.
Mr Rattigan was a member of a large family with a troubled background. An elder brother, Patrick, was stabbed to death in a family row In Tallaght in 1991. Patrick Rattigan was 44 when stabbed with a kitchen knife by his stepson Mr Anthony Howard, who said he intervened when his drunken stepfather was using a concrete block to attack another stepson on the pavement outside their house.
Mr Howard, then aged 24, was jailed for five years after being convicted of manslaughter.
Gardai said so far they have no evidence that Tim Rattigan was involved in the illegal drug trade or was a significant criminal, although he had links to one member of the criminal gang run by Martin Cahill, known as The General, who was murdered in 1994.
Chief Supt Bernard Haughey said yesterday that a murder investigation was now in progress based at Kilmainham Garda station. He asked anyone with information which could help find the killers to come forward.
In a statement the new Minister for Justice, Mr O'Donoghue, promised a "relentless Garda investigation" which would not end "until those involved have been arrested and brought to justice".
Mr Rattigan appears to have become embroiled in a personal dispute - the explanation for up to half the gangland killings in Dublin in the two years to the end of last year
His killing had the hallmarks of a professional "hit" of the type which became relatively commonplace in Dublin from August 1994 when Cahill was killed in Ranelagh. The splintering of Dublin criminal activity after his death led to 15 killings, with most of the victims shot in the head at close range.
The last such killings were in December when a drug dealer, P.J. Judge (41), was shot dead outside the Royal Oak pub in Finglas, and Mark Dwyer (23) was shot dead, and his body found in a field in Finglas. The previous September Michael Brady had been shot dead in his car on the inner city quays.
However, increased Garda activity against major drug criminals in Dublin last year, after the murder of the journalist Veronica Guerin in June, was credited with reducing the level of gangland violence.
A number of the major gang leaders fled abroad, hoping to return after the investigation into her murder died down.