The 50-year-old man found dead at a house in Lisburn on Friday night has been named by police as Paul Smyth.
Detectives investigating the suspected murder of Mr Smyth have arrested four people.
Three men aged 49, 32 and 28 and a 28-year-old woman were arrested in the Lisburn area on Saturday evening and remain in police custody.
Mr Smyth was found in his living room at around 8.45pm on Friday night.
Detective Chief Inspector Eamonn Corrigan is appealing for information.
“I am appealing for anyone with information that could potentially assist the investigation to please get in touch by calling 101. Or alternatively, information can also be provided to the independent charity Crimestoppers on 0800 555 111 which is 100% anonymous and gives people the power to speak up and stop crime,” he added.