The bomb was left in a holdall in Exchange Street West where it exploded shortly before 7pm on Friday 13 December when the area was packed with Christmas revellers.
A warning had been given about a device but it was left at a different location to that named in a call to a newspaper. Police were clearing people from several premises when the device exploded. Approximately 1,000 people were affected.
Today police released two CCTV images of a man on a bicycle in Talbot Street and in St Anne’s Square who they believe to be the person who left the holdall containing the bomb in Exchange Street West.
Detective Inspector Chris Wilson, from Serious Crime Branch, said: “These images were taken at 5.46pm when the area was busy. In Talbot Street the cyclist actually moves in the opposite direction to the traffic. In St Anne’s Square the holdall is visible beside the bike’s handlebars.
“Our inquiries are progressing. We have established that a pressure cooker was used as part of the device. The attack ruined a night out for hundreds of people but it had the potential to injure or kill.
“Anything you saw or heard may be of assistance. Or if you know anything about the attack or the cyclist, please contact us.”
Anyone with information is asked to contact detectives at 028 9180 1507. Alternatively, information can be provided anonymously to the independent charity Crimestoppers on 0800 555 111.