Police investigating the murder of Stephen Davidson in Bangor, Co Down last weekend have released a 49-year-old man and a 61-year-old woman they were questioning.
The two have been released pending a report to the Public Prosecution Service.
A 40-year-old man remains in custody helping police with the inquiry.
Mr Davidson, 31, was found dead at his house in the Ballyholme Road area of Bangor by a relative on Sunday evening.
Tests carried out on an unidentified substance found at the crime scene have established it posed no risk.
Police evacuated the scene earlier as a precautionary measure.