Police have now confirmed an 11-year-old boy and his mother died after their View Street house caught fire in Manapouri on Thursday (4 Jul).

They are also satisfied nobody else was home at the time of the fire, after confirming a third person who lived at the address was at work.

A specialist search team was used in the investigation.

Emergency services were called to the property about 3.40am on Thursday and were alerted that people may still be inside.

Detective Sergeant Mark McCloy said that since then, a methodical investigation has been under way to account for the occupants of the address.

The thoughts of everyone involved are with the victims’ whanau, who are being supported at this tragic time, he said.

"We would also like to thank members of the community for their concern and care."

Police and Fire and Emergency New Zealand will continue to examine the scene over the coming days and this work includes establishing whether anyone else was inside the house at the time of the fire, he said.

Its cause remains under investigation.

McCloy said further details will be provided when they become available.