A building on a property at the centre of a vigilante search for the remains of missing woman Breanna Muriwai was damaged in a “suspicious” fire, police say.

A convoy of vehicles travelled north from the Kāpiti Coast today towards Mangaweka, south of Taihape yesterday afternoon as part of the ongoing search efforts organised by Muriwai’s mother, Jasmin Gray.

Gray had posted on a traffic updates Facebook page to warn commuters of “delays” and “mass congestion” on State Highway 1.

She claimed to know her daughter’s remains were in the area, and had organised a vigilante search supported by locals for information.

In a post to Facebook on Sunday evening, Gray said: “We’ve all had a massive day today and we can say that we have found items of interest”.

She added that they were now waiting on authorities to do “their mahi”.

That same evening, emergency services were called to the rural settlement of Rangiwahia, about 20km from Mangaweka, following reports of a fire.

A Fire and Emergency NZ (Fenz) spokeswoman said they received calls to a house fire about 5.50pm. Upon arrival, fire crews found a single house and shed on fire.

”It was unoccupied at the time,” the spokeswoman said.

Police today confirmed the blaze was being treated as suspicious.

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“The property had been vacant for a number of weeks. Enquiries are ongoing.”

A photo of the fire was posted to a local community Facebook page last night, with the caption: “That house has had some action today, now it’s up in smoke”.

The mass search of the property yesterday followed a warning from police against the action, saying it may destroy or compromise crucial evidence.

A police spokesperson yesterday said while they understood people were genuinely intending to help, the best thing the public could do was “talk to us”.

“Police are still treating her disappearance as a missing persons investigation,” Detective Senior Sergeant Dave Thompson said.

Muriwai, who was 22 at the time of her disappearance, was last seen in August 2022 at Te Horo Beach. Searches were carried out for her, and her movements on the night she disappeared were examined by police.

Jasmin Gray holds a photograph of her daughter Breanna Muriwai. Photo / Woman's Day

Despite an extensive investigation and tireless searches by Muriwai’s loved ones, she has not been seen since.

“We know people want to help and the motivation behind today’s search is well-meaning, but our concern with private searches is the risk that crucial evidence is inadvertently destroyed or compromised, and that’s something we communicated with Breanna’s family ahead of today’s activity,” Thompson said.

“The most valuable thing you can do is talk to us if you have information that may help.”

Gray responded to the statement by saying; “This is the only search you’ve ever tried to stop! Why?”.

A member of the search party posted a video online depicting the convoy driving on rural roads and through the Mangaweka township.

“Feels yucky when we hit here. Yucky feeling, very secluded,” they said, referring to the area where it is alleged Muriwai’s remains may have been taken.

Other videos showed Gray addressing the crowd, telling them what to look for.

Missing 22-year-old Breanna Muriwai was last seen on Te Horo Beach in August 2022.

“She was wearing a red tiger eye bracelet… she was carrying house keys… any house keys [you] find out there just pick them up.”

She reminded the crowd to wear gloves so all the findings could be handed to the police as evidence.

A local business told the Herald there were “a lot of people on the scene” and a police officer was helping to reduce traffic congestion.

Police stressed they continue to investigate the disappearance.

“The fact Breanna remains missing after two years is an unbearable thought and something no family should ever go through. We want to assure the public that investigators continue to follow up leads from the public and the investigation is very much active,” Thompson said.

“We speak regularly with Breanna’s family, following up on information provided by them and members of the public.”

Any information that could assist inquiries should be reported to police online or via the 105 phone service, using the reference number 220829/5320.

Information can also be provided anonymously via Crime Stoppers on 0800 555 111.

Muriwai’s mother made a Facebook live post last year, just before the one-year anniversary of her daughter’s disappearance, saying police had told her “she’s not coming home alive”.

In the post, Gray told more than 5000 viewers about her recent discussions with detectives and shared a recording of a conversation with a man who claimed to have information about a purple suitcase police earlier called “significant” to the investigation.

The purple suitcase police are seeking. Photo / NZ Police

Muriwai was picked up on the Friday before her disappearance by a male friend from Wellington. They travelled to Palmerston North, where they stayed until Saturday night.

The last CCTV images of Muriwai were captured at a liquor store in Palmerston North at about 11.15am on the Saturday.

They began to head back to Muriwai’s home that evening, picking up another man on the way and continuing south. They stopped along the way several times, with a friend withdrawing money from Muriwai’s bank account during one of the stops.

Things became murky when Muriwai and others went to Te Horo Beach.

“Breanna is reported to have run off down the beach and has not been seen since,” Thompson said.

Earlier this month, Gray said she wanted to organise a convoy to farewell her on the Kāpiti Coast.