Three people released in connection with the murder of Robbie Lawlor in Belfast on Saturday have been released unconditionally.
Two men, aged 30 and 33, and a 17-year-old boy were questioned by detectives investigating the murder of the 36-year-old.
A 27-year-old man who was also being questioned was released unconditionally on Monday.
Lawlor, from Coolock in the Republic of Ireland was shot multiple times outside a house in the Etna Drive area.
Police believe a single gunman was involved in the killing.
Lawlor has been linked to the murder of Drogheda teen Keane Mulready-Woods whose dismembered remains were found in various locations of north Dublin in January.
Police are asking anyone with any information about the murder to contact detectives on 101 quoting reference number 562 04/04/20, whilst anyone with CCTV, dashcam or mobile phone footage recorded in the area of Etna Drive and Kingston Court on Saturday is asked to upload it to Major Incident Public Portal, which can be accessed from any device with internet access on https://mipp.police.uk/operation/PSNI20P04-PO1