The shooting dead of Stephen Ledden (28) in Dublin's north inner city marks a "critical point" in an ongoing feud between a number of gangs and families, according to local public representatives.
Speaking to The Irish Timesthey said there was a grave risk of further shootings, and called for an increased Garda presence.
It has also been confirmed that gardaí were carrying out surveillance in the immediate area at the time of the shooting early yesterday.
Independent TD Tony Gregory said it was clear as soon as Gerard Batt Byrne (25) had been shot dead in the nearby IFSC area on December 13th, there was a risk of retaliatory shootings and that "the whole thing could spiral out of control".
Garda sources have confirmed Mr Ledden was one of a number of suspects in Mr Byrne's killing.
Local Labour Party councillor, Aodháin Ó Riordáin, had also warned in the aftermath of Byrne's murder of a spate of tit-for-tat shootings.
"I would just be fearful now that this could get completely out of control and would just appeal for people to be calm and to stop. Attitudes harden as shooting continue and life is increasingly devalued."
Local Labour Party TD, Joe Costello, described the shooting as "an absolutely shocking development".
"All the signs are that this killing was in retaliation for the shooting last week of a man in the nearby IFSC district and I fear this could lead to more attacks, more reprisals and yet more deaths. There is now a risk that this will escalate into a deadly feud."
One man, who has lived in the area all his life, said yesterday it seemed "what has happened is connected to the shooting in the IFSC", as well as an attack on a female from the north inner city some years ago.
Sources in the area say this attack on the woman has led to a feud between a number of families which has become enmeshed in rivalries between gangs, as factions took sides in the matter.
Yesterday, when asked their reaction to the murder, neighbours in the main did not want to comment. All said they had heard nothing. It is believed a silencer was used in the attack.
One middle-aged woman said she heard "not a thing".
"I was sitting here after watching Veronica Guerin on the tele when I saw blue flashing lights flying past the window. I thought it was just an ambulance, but then there were more flashing lights and people coming out on to the street. It's terrible."
Another man, in his 40s, said he was "shocked". "I went to school with that young fella's father. I am just in shock."
A young woman, who did not want to comment on the shooting said: "There's a lot of tension in the area lately."
A Garda van was yesterday parked at the corner of Oriel Street and Seville Place which residents and TDs said had been in the area for the past two months, as part of a surveillance operation as tensions between the rival gangs in the area has increased resulting in the fatal attacks on Mr Ledden and Mr Byrne.
Mr Gregory said yesterday the fact that this most recent gangland shooting took place while gardaí were watching the area underlined how difficult the task facing the Garda was.
"If people are determined to kill each other and they have the wherewithal to do so, it is very, very difficult to stop them."
Garda tape cordoned off the section of Oriel Street around the narrow, three-storey house where Mr Ledden was shot.
Garda forensics experts arrived to examine the scene shortly before noon.
About 45 minutes later children, on bicycles they had got for Christmas, were among those at either end watching as the body of Mr Ledden was taken out on a stretcher, covered in a black sheet, to a funeral director's van.
Gardaí are appealing for witnesses to the killing. Anyone with information is asked to contact Store Street Garda station on 01-6668089.
