One of the first people to arrive at this morning's twin bus crashes near Tekapo has described the eerie sight of multiple bloodied passengers emerging from the foggy wreckage.
Four international tourists have been flown to hospital - two in serious condition - after two buses slid off the road in ice near Tekapo this morning.
Debris could be seen littering the road as passengers huddled together near the buses lying on their sides in thick fog near Lake Pukaki.
Two of those flown to hospital were in a serious condition, while the two others were in a moderate or minor condition.
Wellington resident Felicity Wong said she was travelling with her two sons-in-law, in two separate cars, from Tekapo to Lake Ohau when they came across one of the crashed buses.
The 33 passengers aboard the bus — among them up to 15 children — were still inside but beginning to make their way out, and emergency services had not yet arrived, she said.
One of the passengers on the bus was a doctor, but she herself was injured.
Ms Wong said the bus was "very beaten up and some metres away from the road".
Drivers began "shepherding" children from the bus towards their parked cars, with some taking them inside out of the cold.
"Some of the children had blood on their face and blood on their clothes."
"It seemed that the passengers had sore heads from being banged from the bus rolling, they didn’t have gashes and there didn’t seem to be any glass injuries.
"I think there were a few broken bones."
One of her son-in-laws was a road policing officer, and was the fifth car on the scene, Ms Wong said.
The other was a doctor, and he went to assess the injured passengers.
The passengers were all wearing puffer jackets, and drivers gave children hats and scarves from their supplies.
Ms Wong gave one of them her hot water bottle and handed out Panadol, she said.
"It was remarkably silent, foggy and freezing cold."
"People were just looming out of the fog in shock and the adult passengers were very concerned about the children."
The passengers themselves were "shocked, but very orderly" and emergency services were "really terrific," she said.
"It was a dramatic situation, but people handled it really well."
By the time they left there were multiple ambulances on the scene, she said.
Video of the crash shows a bus flipped on its side, the windows smashed and debris littering the side of the road.
"Oh hell, that would have been scary," a person in the video says.
A police spokesperson said they understood those on the buses were international tourists.
Those not requiring medical attention have been taken to Twizel.
As many as 40 firefighters were earlier working to extract the multiple patients from the two buses, which crashed just 100m apart on State Highway 8.
The separate, single-vehicle crashes happened near the intersection of Hayman Rd and SH8 at about 8.40am, a police spokesperson said.
Both buses appear to have gone off the road on the same side.
A Fire and Emergency NZ spokesperson said about 40 firefighters from Twizel, Lake Tekapo, Omarama and Otematata were at the two scenes.
Hato Hone St John said it was notified of the incidents about 8.38am and multiple units were responding to the scene.
Otago Southland Rescue Helicopter Trust managing director Graeme Gale said they dispatched one helicopter from Queenstown and three from Dunedin, one of which was stood down.
The highway is closed between Tekapo and the intersection with SH80.
NZTA said no detour was available nearby and the road was expected to remain closed for most of the day.
"Westbound travellers should use SH8 east to Timaru, SH1 south to the SH82 junction, and the inland route on SH82 to Kurow/SH83 junction, with westbound to SH8/83 Otematata. Eastbound travellers should use the reverse route."
NZTA Waka Kotahi warned of black ice and winter driving conditions in the area earlier this morning.
A person who works at a nearby business said the roads had been "dodgy" for the past week because of fog.
Another said they seen four police cars go past and heard three helicopters flying overhead, but they appeared unable to land due to thick fog, and believed they were attempting to land near Irishman Creek.
A spokesperson for the Kiwi Treasures and Information Centre, in Lake Tekapo, said there were "consistently emergency vehicles coming past" and they had heard sirens.
Twizel Community Board member Tracy Gunn said the Hayman Rd intersection with State Highway 8 was "notoriously bad"."It’s bad without all the black ice and fog."
People who lived in the area were used to the conditions and knew to drive pretty slow and be careful with braking, but tourists coming to the area would have "never driven in these conditions before" and it could be more slippery than one would think, Ms Gunn said.
Because the area was by the lake, the road generally stayed wet overnight.
"With the freezing temperatures, it just turns it into an ice skating rink."
