The names of the dead were released last night after their bodies were removed from the family home at 65 Every St.
They were Taieri Beach school principal Robin Irving Bain (58), his wife, Margaret Arawa Cullen (50), and their children, Arawa Mary Cullen-Bain (19), Laniet Margaret Bain (18) and Stephen David Bain (14).
The only surviving member of the family, David Cullen Bain (22), found the bodies of the dead about 7am after returning from his Otago Daily Times paper round.
He spent last night with relatives after helping police with the homicide inquiry earlier in the day.
A squad of 35 detectives, led by Chief Inspector Peter Robinson, of the Dunedin CIB, is investigating the slayings.
Mr Robinson said the incident "had domestic overtones".
"We are not looking for anyone else at this stage," he said.
No charges had been laid.
FIREARM FOUND
He would not say who owned the firearm found in the house, but said it was registered to a member of the Bain family.
The shootings are believed to have occurred between 6am and 7am yesterday.
All the victims had been shot in the head. Some were found in their beds, others beside their beds.
The body of Robin Bain had been found in the lounge of the large, run-down twin-gabled villa.
A .22 rifle with a silencer attached had been beside his body, police said.
David Bain had called ambulance services to the house about 7.15am, police said. However, the young man was in a severe state of shock and was unable to open the door to emergency services.
Police had to force the door of the house.
Residents spoken to by reporters in the quiet bush-covered neighbourhood did not hear any shots.
Shocked friends and neighbours yesterday described the Bains as "quiet and likeable" and a family that "kept to themselves".
A neighbour described Margaret Cullen as an extremely social and active person, virtually the opposite to her husband, who was quiet and reserved.
For the past two years Mr Bain had lived weekdays near the Taieri Beach School where he had been principal for almost four years. He commuted to the family home at weekends in his Commer van.
The family had returned to Dunedin about five years ago from Papua New Guinea where Mr Bain had been teaching since the mid-1970s.
The family was heavily involved in music and Mr Bain and his son, David, were members of the Royal Dunedin Male Choir and the Dunedin Opera Company.
Mr Bain was also a former member of the Andersons Bay Primary School board of trustees.
The three dead children had attended Bayfield High School and yesterday the principal, Bruce Leadbetter, said the school was devastated by the tragedy.
"They were really a special family, a very talented family - the whole lot of them. They were musical, involved with theatresports and drama, and, you know, just one of those groups of just special people. So it's a very devastating situation."
In his "wildest nightmares", he would never have expected such a tragedy to hit the Bain family.
Stephen, a fourth-form pupil at Bayfield, played trumpet in the school jazz band and performed in the school musical production earlier this year.
Arawa Cullen-Bain, nine days short of her 20th birthday, was head girl at Bayfield in 1992 and was in her second year at the Dunedin College of Education.
Residents at the nearby Karitane Rest-home were also shocked by news of the killings.
A nurse aide at the home, Tania Clark, said the first she knew something was wrong was when she saw six police cars and three ambulances converge on the house shortly after 7am.
The quiet neighbourhood was cordoned off by police early in the morning with road blocks at the top and bottom of Every St.