He claimed the debris from the vehicle sparked a fire on the side of the road.
Donnoly pulled over and phoned 111 to report the growing fire.
“At the same time, a policeman pulled over and was trying to put out the fire that was starting,” he said.
“It started as a little puff of smoke and then they were big balls of flames shooting up the grass, into the bush.”
He estimated the fire ignited within a few seconds.
“Everything is tinder dry and it happened right next to where the last one happened.”
The fire disrupted Donnoly’s work as a shuttle driver for the Tongoriro crossing.
“I have lost four or five days’ worth of work, maybe. If I don’t work, I don’t get paid,” he said.
“It happened on the first run of the pick-up so there might have been 1000 people doing the crossing that day, that 90% are all coming back to National Park from the walk.
“So you’re having to drive all the way to Waiouru through Ohakune, it’s almost a two-hour journey to bring those people back.”
Yesterday, Fire and Emergency New Zealand incident controller Renee Potae told media that police had informed the organisation they had made good lines of inquiry as to how the fire started.
“It does seem to be unintentional, a misstep with a vehicle basically.”
Yesterday afternoon, Fire and Emergency New Zealand announced the fire had been fully contained.
By 1.30pm, the fire’s size was 296ha, down from 322ha, with an 8.5km perimeter.
Road access along SH47 is expected to be restored by this evening.
Fire and Emergency New Zealand and Waka Kotahi are due to reopen the road with speed restrictions and potentially a single lane under stop/go controls from 9pm.
Fire trucks are still likely to be moving through the area for at least another 24 hours, with Potae asking all drivers to observe the traffic controls to ensure the safety of all road users.
She said reopening the road was a significant step for the community and visitors.
Ngāti Hikairo ki Tongariro has extended the rāhui from the previous fire to all affected lands.
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