Investigators have found a fatal house fire in Southland last week was caused by a heater.
The bodies of a mother and an 11-year-old boy were found on Friday, a day after the fire at a View St property in Manapouri.
Police earlier said other people remained unaccounted for, but they were now satisfied no-one else was at home at the time of the fire.
Fire and Emergency district manager Julian Tohiariki said a heater likely came into contact with bedding, and the house had no working smoke alarms at the time.
Detective Sergeant Mark McCloy said forensic specialists were helping to identify the bodies, which have since been taken to Christchurch.
"Following the initial examination, police along with specialist fire investigators from Fire and Emergency New Zealand conducted a full scale scene examination of the home over the weekend."
McCloy earlier said neighbours tried to rescue the pair.
"Neighbours at the property attempted valiantly to gain entry to the burning house, but they were unable to and contacted emergency services," he said.