Published Monday, 28 October 2013
The man is being questioned by police. (© UTV)
David Hamilton was attacked at his home in the Ballybeen estate, on the outskirts of east Belfast, almost nine years ago.
Three men have already been convicted of the murder.
Detectives from the PSNI's Serious Crime Branch detained a 37-year-old man in Bangor on Monday morning as part of their investigations.
He was questioned at Bangor Police Station and released later that day pending a report to the Public Prosecution Service.
Mr Hamilton was 40 when the attack happened in November 2004. The hospital porter suffered multiple head injuries after being beaten at his flat in Gleneagles Gardens.
© UTV News