Ryan Lee, 19, was shot twice by the man who entered Brannigan’s on Mulgrave Street at approximately 9.30pm.
Gardaí believe the gunman may have been looking for the bar’s owner, Stephen Collins, but shot Mr Lee by mistake, as both were wearing similar black shirts.
After the shooting, the gunman, who was wearing a helmet, calmly walked through the crowded bar before being driven off on a motorbike. More than 300 people were in the bar and function room at the time.
The man is the leader of one of the city’s most feared feuding gangs, based in Ballinacurra Weston.
The gunman was seen near the pub before the shooting. A number of his associates were seen near the premises while others were in the bar.
“We are looking at all CCTV to see if there were any events in the premises or outside,” said a garda source. Gardaí have already spoken to the main suspect.
Mr Lee was in stable condition at the Mid-Western Regional Hospital last night after operations yesterday to remove two bullets from his groin and knee.
He has lived with the Collins family in Monaleen since the death of his parents. Neighbours say he is like one of the family and refers to Mr Collins as “dad”.
He is a full-time barman in Brannigan’s, which Mr Collins purchased a few years ago after moving back from England.
One witness, who asked not to be named, said: “The bar and the lounge were packed. The front door of the bar was closed, but the door to the function room, which was packed as well, was open. The gunman, who was dressed in black and wore a balaclava under a helmet, appeared inside the bar counter. He must have come in the function room front door.
“He approached Ryan inside the counter, pointed the gun at him from about three feet and fired two shots,” the witness said.
The gunman then walked out the door on to Mulgrave Street and jumped on to the back of a waiting motorbike.
As the bike sped off, the gunman fired at Mr Collins as he rushed out the door after him.
Mr Collins was unhurt.