Mark Fagan, 20, was shot at close range in a field in Cherry Orchard, Ballyfermot, west Dublin, just before 10pm on Monday.
A short time afterwards two cars were stopped by elite Garda units on Ballyfermot Road and five men were arrested.
The operation was conducted by the Organised Crime Unit, assisted by the Emergency Response Unit.
Gardaí are satisfied that the five men were involved in one way or another in the shooting.
Most of the five are well known to officers.
Officers intend to charge up to four of the men in relation to travelling in a stolen car.
Further, more serious, charges may follow once a complete file is sent to the Director of Public Prosecutions.
Senior officers were in contact with the office of the Director of Public Prosecutions last night.
Mr Fagan was involved in one of two feuding gangs in the Crumlin-Drimnagh area of south Dublin.
Officers suspect he may have been shot as he was seen as a “soft target”. Both gangs have been increasingly targeting fringe members of the gangs, and their innocent relatives, in the spiralling feud.
Detectives are also investigating suspicions the shooting might have been linked to a drugs debt or missing drugs.