A man in his 20s has been arrested in connection with the murder of Paddy Lyons in Waterford.
He was arrested Monday afternoon and is currently being detained at a Waterford garda station.
He is being held under section 4 of the Criminal Justice Act.
The body of 90-year-old Paddy Lyons was found at his home in Ballysaggart at around 5.00pm on Saturday evening.
He was pronounced dead a short time later.
His body was later removed to Waterford University Hospital for a post-mortem.
Gardaí announced Monday that their investigation had been upgraded to a murder inquiry.
Meanwhile a man and woman who raised the alarm, and were sought in an earlier media appeal, have come forward.