Police are making a new appeal for information on two house fires - one fatal - in Upper Hutt a year ago.
Margaret "Terri" Fordham, 75, died after a fire in her house on Bridge Road in Birchville, just before 2am on 12 August, 2021.
Neighbours tried to rescue Fordham but did not reach her in time.
"Her last act was to throw her dog Daisy to safety before she succumbed to the smoke," detective sergeant Sam Mercer said.
Two nights later, on 14 August, another blaze broke out at the same house at 3.30am.
It caused significant damage to the second storey, where Fordham was found in the first fire.
The cause of the first fire is undetermined, but the second is being treated as suspicious.
Police believe someone deliberately started the second fire, Mercer said.
"We are following up every possible line of inquiry to identify that person, but we need the help of the public who might hold important information," he said.
"The person responsible might have talked to a family member or friend about the fires, or displayed some behaviour which causes concern."
At the time of the fires, the country was only days off from moving into a level 4 nationwide lockdown, Mercer said.
"This is a really tragic situation in which a much-loved mother and friend has lost her life."
Terri Fordham's son, Kester, said her last act of saving her dog summed up who she was.
"We haven't had a chance to mourn her properly, or move on and I still wake up and realise that it has actually happened, and it wasn't a dream," Kester said in a statement.
"Nothing is going to bring mum back, or fix it, but finding out what happened would help us understand why, rather than just being left wondering, doubting and questioning things."
Anyone with information should ring 105, and quote the file number 210812/6583 or, if they want to remain anonymous, ring Crime Stoppers on 0800 555 111.