Emergency services are refusing to say what caused an explosion at a Kāinga Ora-owned Invercargill home yesterday.
Emergency services were called to the Rothesay Place house in the suburb of Rockdale shortly before 1.30pm yesterday following reports of an explosion.
Fire and Emergency New Zealand (FENZ) found the kitchen and dining room on fire and assisted three people from the home with burns.
St John took two people to Southland Hospital with serious injuries, where they remain in a stable condition.
A third person received treatment at the scene for minor injuries.
A specialist fire investigator has looked into the cause of the fire, but FENZ are referring any further comment to police.
A police spokesperson said the fire itself was not being treated as suspicious.
However, they confirmed detectives were investigating the matter.
"We are looking into the circumstances of it," the spokesperson said.
Police would not comment on the cause of the fire or the explosion, nor would they comment on why detectives were investigating a fire which was not deemed suspicious.
Police would also not say whether any charges would be laid against the occupants.
The house is uninhabitable as a result of the fire.