Republicans were being widely blamed for the killing of the IRA informer and author Mr Eamon Collins, whose body was found on the outskirts of Newry, Co Down, early yesterday morning.
However, even experienced observers were having difficulty in pinpointing the element in the republican movement most likely to have carried out the killing.
Last night, the RUC said it was treating the death of Mr Collins as murder. A post-mortem yesterday evening showed among other injuries - including severe head wounds - there were a number of stab wounds to his body.
Observers believed if a killing had been ordered by the Provisional IRA leadership, Mr Collins would have been shot.
The manner of his death - he had multiple head injuries and initially appeared to have been hit by a car - suggested that it was either an "unofficial" operation, possibly based on a personal agenda, or it was not meant to be traced to any particular group.
There was some suspicion dissident republicans, who incurred strong criticism from Mr Collins, might have been responsible for his death.
Mr Collins's body was found at 6.20 a.m. at Doran's Hill, a country road located a few hundred yards from his family home in the nationalist Barcroft estate in Newry. Multiple head injuries made it difficult to identify him.
Before the post-mortem results became known yesterday, the Sinn Fein president, Mr Gerry Adams, said: "I have no reason to believe that Mr Collins's death was anything other than accidental."
Mr Collins (45) was married with four children. After a heart bypass operation he took regular morning walks as part of his therapy, but it is understood he was not in the habit of going for walks as early as 6 a.m.
He was badly injured in a hit-and-run incident in early 1997 and last year a house belonging to him in Camlough, Co Armagh, was burned down.