A former SAS tracker says police need to be using a specialist army team to hunt out Marokopa man Tom Phillips and his three children.
Phillips, who is not the children's legal guardian, has been AWOL with Jayda, Maverick and Ember for two-and-a-half-years.
Now police are offering an $80,000 reward for information leading to the children's safe return.
Phillips is a suspect in a Te Kuiti bank robbery, and allegedly tried to smash his way into a Piopio superette - possible with one if his children.
Former SAS tracker speaks on Tom Phillips hunt
The police believe someone is helping them stay hidden in the Marokopo area, where there is now a strong police presence and a two-week deadline to collect the reward.
Barrie 'Baz' Rice, a former SAS commander and tracking instructor, explained to Checkpoint on Thursday what tactics the police might be using to find them.
"What I would do is I'd put an SAS tracking team in there before it gets contaminated with too many other sort of tracks and signs, or the weather gets to it," he said.
"And then I would start to try and find it and see where it leads back, to where it came out - well, where they would have come out of the bush - and then follow it that way.
"And at the same time, [use] other patrols to do map recons to have a look around… send other people off to sort of find the possible locations they could use to build a base. Because if they're around that area, they're going to have to have a base of some description."
Marokopa in the King Country. Photo: RNZ / Marika Khabazi
There was an alleged sighting of the father and the children a couple of weeks ago in the thermal pools at the Okoroire Hot Springs Hotel, about two hours' drive from Marokopa - potentially a clue to their hideaway.
"It depends on what time the… eyewitness saw the people in the pools - because if it was late in the afternoon, they wouldn't be too far away from there because there's no way you'd want to be walking around in the bush at night. But if it was in the morning that would give them more time to get back further away."
Wherever they are they would need to have accessible water, he said, and there would likely be visible tracks.
And their 'base' might not be as comfortable as you might expect.
"I wouldn't necessarily have to be a physical building as such. It could be a mine shaft, it could be caves, it could be something out there that people knew about back in the day but people now don't necessarily know about, because hiding in a shack or whatever else is kind of a bit obvious.
"So I wouldn't just be looking for something man-made that they're living in."
Rice said police would be using different strategies in this case to what they would use to find a lost person.
"I'd be a little bit more surgical. I mean, they're in no great hurry I would imagine. Now, as long as they're going to cordon off the area that they do it quite a ways out from where they are, and then as the tracking team goes in, they can bring it in closer and closer until they encircle them.
"But I'd resist the urge to put a whole lot of people in there looking for them, because all they're going to do is make a mess of the ground and then it's going to be so difficult for a tracking team that they wouldn't find them because there'd be too much contamination."
Barrie 'Baz' Rice. Photo: supplied
He would go with two or three teams of just four to six people at a time, swapping out regularly to avoid exhaustion.
Other clues would be things like smoke from a fire, and markings on trees above where most animals could reach.
"There's a lot of things that you take into consideration when you're tracking people that humans will leave behind and animals won't."
The big disadvantage Phillips had in staying hidden would be the children, Rice said.
"Would probably slow them down… wouldn't be as conscious or concentrated to be able to hide their track the whole time… And if there's four people, that's a lot of signs they're going to be leaving."
Information flowing in
Police said they have been continuing to receive and assess information today as they seek the safe return of the three children.
"We have concerns for the welfare of the children who have been living in isolation for the past two-and-a-half years, with no connection to others and without formal education and health care," Acting Detective Inspector Andrew Saunders said.
He urged anyone with credible information to get in touch.
Anyone wanting to contact them can do so by emailing op.curly@police.govt.nz, calling 105 or filing a report online, using the reference number 211218/5611.
Saunders also acknowledged Marokopa residents coping with the disruption as search efforts continued and thanked them for their understanding.