Seven months on from the grisly killing of teen Ariki Rigby – and her body being torched in a car in a rural carpark – her family have spoken of their anguish over the protracted investigation and a lack of “confidence” in the police.

Police launched a homicide investigation into 18-year-old Ariki’s death last September, and shortly before Christmas said they believed gang affiliations of those thought to be responsible were preventing possible witnesses from passing on vital information.

And today police say the inquiry is at a “sensitive stage”.

But the launch of the hunt for those responsible was a belated one.

Police were first alerted to the burned-out car at River Road Recreational Reserve on September 3. The Herald revealed officers who attended didn’t realise the charred remains inside – which featured shoulder-length hair and a necklace – were human, instead thinking it was a sheep.

It wasn’t until September 5 that dog walker, Kevin Monrad, realised the remains were human after walking around the burned-out car, then urged police to return to the scene.

Ariki Rigby was working in a bar in Auckland before going on an unplanned holiday to Hawke's Bay when she was killed.

By then, the crime scene had been traipsed through for 48 hours by scores of dog walkers, cyclists and others who visited the popular reserve.

Seven months on from Monrad’s call, Ariki’s cousin and initial Rigby family spokesman Michael Ngahuka said the slow progress had him questioning if those responsible would be found.

 “You lose confidence in the police,” the Hastings-based pastor said.

“There was no confidence in the police, to begin with. You are hoping they will do their job - they probably are, but what does it look like for us?”

A memorial garden with written, floral and solar light tributes to murdered teen Ariki Rigby has been erected at the River Road Recreational Reserve carpark. Photo / Neil Reid

Police revealed last year that they were reviewing their initial response. The outcome has not yet been made public.

Police HQ has not responded to questions about any outcome of that review.

In a recent interview with the Felon Show on YouTube, Ariki’s sister Anaherā Rigby said those responsible for Ariki’s death had chopped off her hands and feet before they torched her body and the car she was stuffed in.

She previously told the Herald that she believed Ariki was killed by multiple “gang-affiliated” people.

“For them to get away with it, there must have been a lot of them. And still, to get away with it, they must have had a plan. If the police can’t find them now, obviously it [Ariki’s death] was not an accident.”

Ngahuka has also previously described his cousin’s death to the Herald as a “heinous crime” which he believed “has to weigh on the soul, it has to weigh on your heart” of those responsible and those who know the truth”.

The location where the car containing Ariki Rigby's body was torched is a popular destination for dog walkers. Photo / Neil Reid

Seven months on, he said the Rigby family were desperate for the truth to emerge and for those responsible to face justice.

“It is the same message, if you know anything come forward,” he said.

“Front up if you know something. The family want the case closed, they want to see the other side of this.

“Some whanau members are finding it difficult and hard.”

On December 22, Detective Senior Sergeant James Keene made a public appeal for those who knew who had murdered Ariki – and, in a completely unrelated case, who beat Flaxmere man Eddie Peters to death in November 2018 – to come forward.

“We know there are people in our community who know what happened to Eddie and Ariki, and who was responsible,” Keene said at the time.

“We also know there are a few reasons why people might not be talking – one of which is a belief that ‘narking’ is not the done thing. My plea is that people set aside that belief and focus on what the right thing to do is.”

Family of Ariki Rigby have placed flyers in shops around Hastings and Flaxmere appealing for information about the teen's murder. Photo / Neil Reid

Ngahuka said he had hoped police would share more on the potential gang involvement.

“There possibly is [gang involvement]. You just don’t know. Something like this [the nature of the crime], you have to say there is something wrong with you.”

Ariki’s social media posts contained many references to the Mongrel Mob, including staunch support for the gang.

One of her final posts in August featured her with several of its members.

Ngahuka said in some cases the links to gang members were blood-based.

Ariki Rigby's sister, Anaherā Rigby, along with their cousin Hastings-based pastor Michael Ngahuka.

“All of our family are part of different gangs,” he said. “There are cousins, uncles [in gangs] . . . and that is in more than the Mongrel Mob, other gangs.”

The Herald put Ngahuka’s comments to Police HQ for comment.

A spokesperson said that police remained committed “to holding the person or persons responsible for Ariki’s death to account”.

They were in touch with the Rigby family’s “nominated family spokesperson” with any updates.

“At the moment our focus remains on the active investigation into Ariki’s death, this includes analysis of all evidence to date. We reiterate that the investigation remains at a sensitive stage and we are continuing to make progress.”