Detectives are closing in on a prime suspect for a reckless gangland-style gun attack in a busy pub, it has emerged.
Paul Cullen was shot dead in front of his wheelchair-bound father in the Cabra House pub on Fassaugh Avenue, Cabra, north Dublin, shortly after 7pm on Sunday March 3.
A cash reward is being offered to anyone with information which significantly helps the investigation.
Detective Inspector Colm Murphy said the smallest amount of information could close the case.
"It was a cold, callous calculated murder that happened in a public house with patrons, family members and friends of the deceased in the pub," he said.
Senior sources said detectives have established a motive for the gun attack on the father-of-one and are focused on a prime suspect from the locality.
"We know who he is, we just need to get him in," he said.
The victim was known to gardai and was previously connected with a gang run by murdered gangland boss Eamon Dunne, known as The Don, who was shot dead in the nearby Fassaugh House Pub in April 2010.
Detectives have trawled through CCTV from in and around the bar to piece together the movements of the gunman and motorbike used as the getaway vehicle.
No arrests have been made to date and no handgun recovered. A cash reward is being offered to anyone who calls Crimestoppers on 1800 25 00 25 with information which significantly helps the investigation.