Police are appealing for witnesses to the fire at Six60's former flat which forced a man to jump from a window to safety at the weekend.
In a statement today, police said they were "continuing to investigate'' the blaze at 660 Castle St which happened about 6.30am on Saturday.
A police media spokeswoman would not confirm that the blaze was being treated as suspicious.
A scene examination was continuing and police were working closely with the Fire Service, the statement said.
Police want to speak to motorists, cyclists and pedestrians in the vicinity of Castle St and Cumberland St between 6pm on Friday and 7am on Saturday.
Senior Sergeant Ian Temple would not confirm to the Otago Daily Times today if the fire was being treated as arson.
Specialist fire investigator Mike Harrison referred all questions to police while officers were still carrying out inquiries.
University of Otago student Robby McPhail, 19, suffered burns and lacerations to his hands as a result of the fire, and broke his left ankle after leaping to safety from his second-floor bedroom.
Two other residents were taken to hospital with minor injuries including smoke inhalation, cuts and bruises.
Firefighters discovered smoke detectors stowed in a cupboard.
Campus Watch staff were going door-to-door this week ensuring that student flats had working smoke alarms after the potentially fatal fire.
The house at 660 Castle St is the former flat of Kiwi band Six60, who formed and regularly played gigs there.
Both the band and Castle St hit headlines in March when a balcony collapsed during the band's annual gig, injuring 18 people.
Up until this year the band held an annual gig at their old flat, but due to limited space they moved their show this year to 598 Castle St.