Two teenage boys were found wet, hungry, and shivering uncontrollably in the Kaimai Range by police officers who say if they had not found the pair then, they could have died.
The 17-year-olds were biking the ranges between Tauranga and Waikato when one of their bikes broke down.
Night-time was approaching but the pair had no warm clothing, torches or equipment to stay in the bush overnight.
One of the boys' phones had died, while the battery of the other was down to 3 per cent.
The teenagers managed to call for help using the remaining cellphone battery, alerting St John who in turn told the police.
Officers used the phone's "mobile locate" function to determine the youths' location on the track, which was about a kilometre from the top of the Waikato side of the ranges.
"By the time we tried to get in contact the phone was completely flat and we had no contact with them," Senior Constable Peter Karam said.
Conditions were cold with showers and southwest winds.
Karam, alongside Constable Paul Roberts, walked two hours into the bush to the teenagers' last known location.
They blew whistles and flashed torches until one of the boys called out.
Hungry, damp and wearing only light cotton clothing and shorts, the pair were borderline hypothermic when they were found 100m off the main track.
"If we hadn't got them out that night, there could potentially have been a fatality – they would have gone downhill pretty quickly," Karam said.
"They were absolutely overwhelmed and grateful."
The officers gave the youths warm clothing, raincoats, hats and food and they all began the hike out of the bush.
"Once they started moving and got out of the wind, were dry and had some food they perked up pretty quickly."
The boys met their families - who were waiting with hugs - around 1.30am.
"People need to take enough gear with them so that if they had to spend a night in the conditions if something unforeseen such as a breakdown, or an injury were to occur," Karam said.
He recommended always taking quality warm clothing, a raincoat even if it's not raining, hat and gloves, extra food, a torch and a fully charged cellphone.
A personal locator beacon was always useful, along with a small first aid kit, map and compass if going anywhere off track.