A father of four has been named as the victim of arson at a property in the Ruapehu district of Waitaanga last month.
He was 55-year-old Sidney Ross Bridson.
Detective Senior Sergeant Gerard Bouterey said extensive DNA testing had been done to determine it was Bridson.
Fire and Emergency NZ were called to the house fire on Waitaanga Road around 7am on 11 October.
Bouterey said the home was "extensively damaged" by the time firefighters arrived and a body was later located at the scene.
Investigations determined the fire to be suspicious and a homicide investigation was launched.
Bouterey said the severe damage to the home made the investigation "an incredibly difficult one".
"Central District Police are working hard to determine what occurred and hold those responsible to account," he said.
"Police remain in contact with the victim's family and they are being supported by Victim Support where needed."
As a result of the investigation, two search warrants have been conducted by police - one in Waikato and the other in Waitaanga.
"As part of the investigation, police are wanting to speak to anyone who was in the Waitaanga Road area between Tuesday 10 October and Wednesday 11 October.
"A number of trucks and private vehicles travel the road frequently and would have transitioned through the area on the day prior to and day of the arson."
Bouterey said police are also wanting to talk to the driver of a while ute that was allegedly seen driving on Waitaanga Road around 8pm on 10 October.
"He is not a person of interest but police believe he may have information that could help our investigation."
Police had spoken to a number of people in relation to the investigation - but were extending their appeal.
Anyone in the area of Waitaanga Road between 10 October and 11 October - who had not already spoken to police - was asked to get in touch.
Police could contact police by calling 0800 287 453 or going online, referencing file number 231011/2157.
Alternatively, information can be given anonymously via Crime Stoppers on 0800 555 111.