However, Southland fire and police investigators were unable to confirm if the blaze at the property in Clifden Gorge Rd, Eastern Bush, was suspicious.
It was reported yesterday there was a link between the owner of the house and missing man Dale Tama Watene (40), who was allegedly the owner’s employee.
However, police were unable to confirm whether there was a link.
A police spokeswoman said yesterday police were still "in the early stages" of the investigation.
Mr Watene was reported missing from the Otautau area on April 17 and is yet to be found.
Invercargill Chief Fire Investigator Murray Milne-Maresca, one of the team of investigators, said "there’s a lot of damage".
He was also unable to confirm whether or not the fire was suspicious.
"Everything’s being treated with extreme care ... it’s like anything, it takes time."
It would take "some time" before any conclusion could be drawn on the cause, he said.
The investigation would continue tomorrow.