Dunedin police are seeking two, possibly three, people seen in the Steamer Basin area the night a young Dunedin man fell in the harbour and died.
Senior Sergeant Trevor Thompson said the death of Regan McCormack (20) on July 10 was not being treated as suspicious.
Investigating police simply wanted to speak to everyone who was in the area at the time so they had the fullest possible information, Snr Sgt Thompson said.
Mr McCormack, a University of Otago student, was believed to have left a friend's 21st party on July 9 to walk to the family home in Waverley, when he became disoriented and fell into Otago Harbour.
His body was discovered by workers repairing a boat at the Fryatt St wharf at 10.50am the next day.
Police would like two males seen near public toilets at Steamer Basin about 4am on July 10 to contact them, Snr Sgt Thompson said.
The males were described as Caucasian, aged 15 to 19.
They may have noticed someone cleaning the toilets about that time, police say.
The car they were travelling in was described as a dark green four-door 1990s Nissan or Toyota.
A third person may have been waiting in the car, police say.
Those people, or anyone who knew them, should call Detective Sergeant Brett Roberts at the Dunedin Central police station, Snr Sgt Thompson said.
