A man murdered in the Glenwherry area of Co Antrim - between Ballymena and Larne – had been shot twice in his home.
The body of 52-year-old David Hugh Murphy was found with two shotgun wounds at his Church Road house at about 1pm on Tuesday.
A friend who had been concerned by a lack of contact made the discovery.
Officers investigating the killing say it is too early to tell if loyalist paramilitaries were involved.
PSNI Detective Superintendent Jason Murphy said: “We know that David was known to the police, we know his mother and father and siblings are still living relatively local to his home, we know he had friends, we know he had friends that lived in the local area …
“What I don’t know at the minute is enough about David and David’s background to assess whether that’s important to the investigation and important to the motive for his murder.”
DS Murphy added that there was absolutely no justification for murder.
“David should have been safe in his home, but someone callously shot him in cold blood at some point over the past few days," he added.
“This was not just an attack on David – it was an attack on his parents and siblings who will have to come to terms with their loss.
“The community in Glenwherry have been deeply distressed by this brutal incident which occurred in this normally quiet, rural area.
“I want to reassure the wider public that there is no evidence that they are at an increased level of risk and we are fully committed to catching David’s killer and recovering the firearm used."