"We are in the very early stages of the investigation and currently have very limited knowledge of what occurred at the scene," Mr Lynch said.
Police were particularly interested in talking to a male and a female seen leaving the premises shortly before police arrived, he said.
"Police need to identify and speak to these two people to ascertain whether they have any information relating to the incident.
"It would be in their best interests to contact police as soon as possible."
The victims had yet to be identified. However, police believed they knew who they were.
No further comment regarding the identity of the victims would be made until their next of kin had been located and identified, My Lynch said.
"If anyone has information relating to the case please call Counties Manukau Police on 09 261 1300. Alternatively information can be given anonymously to the the organisation Crimestoppers on 0800 555 111."