The house, occupied by two women, was completely destroyed in the Friday night blaze.
George Nicholls, the chief officer at Fire Rescue Services, said investigation into the cause of the fire will start today.
Given the recent arson cases in Rarotonga, Nicholls said they could not rule it out as a possible cause to last week’s fire.
“Some of these fire cases look quite suspicious and are not likely to be caused by accident,” Nicholls said.
“People need to secure their homes. It’s a good idea to raise dogs who can guard the property and alert owners of any intruders who might be trespassing with wrong intention.”
Investigators have ruled out electrical fault as the cause after preliminary findings established lights in the house were still on when the blaze broke out.
“We are not sure how long the investigation will take. Luckily the fire was sighted early. If it had fully engulfed the house before the firefighters arrived at the scene, it would have become hard for us to narrow down to where the fire exactly started,” Nicholls said.
Five fire trucks – three from Teimurimotia and two from Puaikura – and about 16 volunteer firefighters attended the fire. They managed to contain it in about an hour.
Nicholls said the fire had spread around the house and was coming out through the windows when the firefighters arrived at the scene.
“The position of the house which was on the hillside made things difficult for the firefighters who had to draw water from downhill to contain the fire.”
One of the tenants was in the house and escaped uninjured after she was alerted to the fire that broke out at about 11pm.
Teimurimotia Fire Station received the call to attend the fire from Rescue Fire Services at 11.34pm.
Chief station officer Alistair Macquarie earlier said the Rescue Fire was unable to attend because of an incoming flight.
Macquarie said they arrived at the scene 15-20 minutes later but had problems accessing the property which was blocked by a car parked on the driveway.