Gardaí are continuing to question four people in connection with the murder of William Stokes in Tipperary.
The 48-year-old married father was stabbed to death as he sat in his van in Tipperary town on Friday evening.
A man and three women are being questioned as part of the investigation.
A 20-year-old man who was arrested for questioning has been released without charge.
One line of inquiry is that the killing is linked to an ongoing feud between members of the travelling community in Tipperary and Waterford.