The body of Michael Healy, 62, was discovered at his apartment in Rocksprings Terrace, St Luke’s on Wednesday. It is understood he had been battered to death.
The 38-year-old suspect was arrested in Passage West on Thursday night and taken to Mayfield Garda Station for questioning. He can be held for up to 48 hours without charge.
The man was being questioned as a team of forensic investigators last night left the flat being rented by Mr Healy, a separated father-of-two who was found dead when his brother went to check on him.
Mr Healy, a native of Grenagh, a village near Mallow in North Cork, died as a result of suffering a number of blows to the head. Efforts to locate a murder weapon have so far failed.
Searches were carried out by the divisional search team in the front and rear garden of the house at Rocksprings Terrace, and on waste ground near the house.
Superintendent Tom Myers, who is leading the investigation into the murder. said gardaí believe an implement was used in the attack.
In an effort to establish exactly how Mr Healy died, gardaí are seeking information about the movements of his taxi cab, a black Toyota Avensis, which was parked outside Henchy’s Bar in St Luke’s, close to his home.
The registration number of the car is 03C4073.
The incident room can be contacted at (021) 4558519.