Published Monday, 16 December 2013
The bodies of Finbar McGrillen, 42, and Caron Smyth, 40, were found in a flat at Ravenhill Court the previous day.
On Monday, a court granted PSN Serious Crime Branch detectives an additional 30 hours to question the 33-year-old.
Speaking at a press conference at the weekend, Detective Chief Inspector Una Jennings said the deaths are being treated as suspected domestic homicide.
A special incident room has been established at Musgrave Street PSNI Station and anyone with information is being urged to get in touch on 0845 600 8000.
Police inquiries are continuing.
© UTV News