A post mortem examination has been carried out on the body of 67-year-old Eugene Gillespie, who died following an aggravated burglary at his home in Sligo last week.
The pensioner, who was a former Eircom employee and local shopkeeper, was found tied up and injured in his home on Old Market Street on Friday night.
He was taken to hospital, where he died on Saturday.
Gardaí are appealing for witnesses who may have seen anything suspicious in the Old Market Street area between Wednesday night and Friday night to contact them.
Local Independent Socialist Councillor Declan Bree has said people in Sligo are concerned about a number of similar attacks in recent months.
Mr Bree said: "While there has been incidents in rural areas I think there is significant concern now in Sligo town that we have had a number of instances of aggravated burglaries in the neighbourhood over the past number of years.
"It strikes me that the person or persons responsible for these attacks are deliberately targetting victims who they obviously know live alone."