A father-of-two was beaten and stabbed to death after an ongoing feud between two families descended into a bar brawl and street fight.
Gerard Delaney became involved in the row in Cork city late last night after a relative phoned and asked him and others for back up in the pub.
He had been babysitting his grandchildren with his wife Mary at his home in the Mahon area of the city.
It is understood the 51-year-old went to the Manhattan bar on Lower Friars Walk after midnight when several relatives became involved in a confrontation with members of the Crinnion family.
Mr Delaney's brother Finbarr had been involved in a court case last month against 26-year-old Robert Crinnion who was accused of stabbing him outside his Cork home in a machete attack last February.
Gardai have been investigating allegations that threats to kill have been made against the Delaney family linked to the prosecution.
Graffiti has been daubed on walls in parts of Cork city stating "Delaney is a rat" and there have also been claims that the family were threatened on posting on the internet. One allegation claimed the IRA would order a killing.
"It has been waiting to kick off," a neighbour said.
Finbarr Delaney was convicted in October 2005 for drugs possession.
The Crinnion family are well known in Cork city for their links to organised crime and drug dealing. Michael Crinnion was shot dead as he stepped outside the Clannad pub on Barrack Street in Cork city in 1995. His brother-in-law Kevin O'Flynn was murdered in a gun attack in 2001.
It is believed Gerard Delaney did not have convictions for serious crime and had tried to keep himself out of the family feud.
Witnesses in the Manhattan bar have told gardai that members of the Delaney family had asked a manager to order the Crinnions to leave the pub last night before the row broke out.
It is understood Mr Delaney and relatives arrived at the pub armed with makeshift weapons including baseball bats and iron bars after midnight.
Gardai said the row broke out inside the bar before it spilled out on to the street and at one stage involved more than 20 members of the two families.
Mr Delaney, from Lakelands Crescent in the Mahon area of the city, was beaten, kicked in the head and stabbed in the head and back.
He was pronounced dead in Cork University Hospital.
Gardai believe that members of the Crinnion family managed to disarm some of the Delaneys.
Two other people were injured in the street fight - an 18-year-old man and a woman in her 20s. Their injuries were not life-threatening.
Two men were arrested at the pub on public order offences and later released without charge.
Investigations are ongoing, a Garda spokesman said.
Detectives have appealed for witnesses to contact the garda incident room in Togher