Shortly after the fire, police found bullet holes from a slug gun in a window of the home that had not been there at the time of the blaze. They were not sure if the two events were connected.
Officers are continuing to investigate the suspected arson and have appealed to the public for help identifying a person of interest.
Pilmer said the person was seen on Raumanga Valley Rd between 4am and 6am the day before the blaze.
They had been wearing dark clothing and a balaclava.
“If you saw this person, or anything else suspicious around that time, we want to hear from you,” Pilmer said.
Police previously called for sightings of a white or silver vehicle seen about the time of the fire.
“We’re making good progress on the investigation, including reviewing a significant amount of CCTV footage,” Pilmer said.
Anyone with information can contact police online or call 105 using the reference number 250924/3224.
Information can also be provided anonymously via Crime Stoppers on 0800 555 111.