MIT detectives investigating the murder of Paul Smyth in Lisburn have confirmed that he was shot.
The 50-year-old was found dead in the living room of his house in Coulson Avenue at about 20:45 BST on Friday.
A 49-year-old man, arrested on suspicion of murder on Saturday, has been released unconditionally.
A 32-year-old man and a woman, aged 28, have been released on bail pending further enquiries.
A 28-year-old arrested over the murder has now been released on bail pending further inquiries.
Police carried out two searches and items were taken away for forensic examination.
They have appealed for information.