Three men have been arrested as part of the investigation into the shooting of Karl Wynne in Tallaght, Dublin last year.
Mr Wynne was shot at St Dominic's Shopping Centre on 30 May.
A motorbike with two men pulled up and a gunman fired five or six shots.
Mr Wynne was on a life support machine at Tallaght Hospital before he died from his injuries on 19 July.
Gardaí arrested two men in Finglas, Dublin this morning and a third man was detained in Co Laois this afternoon.
The suspects, aged 28, 25 and 31, are being held at Tallaght Garda Station.
They are the first people to be arrested in connection with the investigation.