The bus and the car were on fire when emergency services arrived at the scene.

Witnesses to a crash near Te Anau tried to help a man trapped in a car following a crash with a bus, minutes before it burst into flames.

Emergency services were called to the scene on the Milford Road, two kilometres north of Te Anau Downs, just before 3pm on Tuesday.

The bus and the car were on fire when emergency services arrived.

JAKOB YE FRAZER/FACEBOOK The crash site near Te Anau, before the two vehicles were engulfed in flames.

All passengers were out of the bus but police were still working to ascertain who was in the car.

Because of the extent of the fire, emergency services had not been able to search the car for occupants.

A police media spokesman said no-one had been taken out of the car.

BARRY HARCOURT/FAIRFAX NZ Bus passengers are assisted at the Te Anau Medical Centre, following a crash between a car and bus.

NOT A GOOD CORNER

Garage door installer Jakob Frazer, 17, of Invercargill, said he and a colleague were returning from doing some work in Milford Sound when they came across the crash.

"When we came around the corner, we must have been there 30 seconds after it happened," he said.

JAKOB FRAZER The scene of a collision between a bus and car, near Te Anau.

"It's not a good corner to see around."

There was a person helping people off the bus, and Frazer went to assist those around him before trying to help the driver of the car, he said.

He was not sure if there was more than one person in the car, as there was an arm "out the passenger door", he said.

BARRY HARCOURT The scene of a crash between a bus and car near Te Anau.

"All I could see was an arm and he [the driver] was screaming for help," he said

The person in the car was "definitely a male" and Frazer thought he may have been from overseas, as he sounded like he had an accent.

"It was just the way he was asking for help," he said.

BARRY HARCOURT The scene of a crash between a bus and car near Te Anau.

"I don't think he was understanding anything that we were saying."

When he arrived at the scene, the car was upside down and the bus was on top of the car, but they were not on fire.

"Then all of a sudden 10 minutes later smoke started coming out from under the engine of the grey car," he said.

He and some other people at the scene tried to put it out with a fire extinguisher, but were not able to put out the fire.

"A couple of minutes later everything's in flames," he said.

"I'm just really shocked."

APPEAL FOR WITNESSES

The road was closed in both directions following the crash, and re-opened just before 11pm.

The serious crash unit and the commercial vehicle investigation unit were investigating, and police are appealing for any witnesses to the crash to contact them.

Fire Service communications shift manager Riwai Grace said the car and bus were both on fire and it was "well involved".

Three fire engines, from Lumsden and Te Anau, were sent to the scene.

A police communications spokesman said there were initial reports that one person was trapped in the car.

Police said all passengers who were on the bus were out and some who had minor injuries had been taken to a medical centre in Te Anau, The other bus passengers have been picked up by other buses that were nearby, police said.

"WE'RE ALL IN SHOCK"

Explorer Tourlines Ltd owner Stephen Cook said the crash involved one of the buses from his company.

The bus had left Queenstown heading to Milford Sound on Tuesday morning and was heading back to Queenstown when the crash happened, he said.

There were 16 Korean tourists on board, he said.

He had not heard anything about any passengers in the car, he said.

"We're all in shock, we're just really grateful none of the passengers [in the bus] were injured."

The man driving the bus had been with Explorer Tourlines for four years and Cook considered him to be of considerable experience as a bus driver.

'CHALLENGING' ROAD

Southland district councillor for the Mararoa-Waimea ward Ebel Kremer said he welcomed any sort of education for people driving in Fiordland.

There was "room for improvement" on the Te Anau-Milford highway, as the "challenging" road was narrow and windy in parts, Kremer said.

There had been suggestions that the road could benefit from having some lay-bys put in, areas where drivers could pull over to let vehicles past or to take photos, he said.

"That has been in discussion for a period of time and some of those suggestions have been put to NZTA [Transport Agency]," he said.

Sometimes visitors to the area did not realise it took two-and-a-half to three hours to travel from Te Anau to Milford Sound, and when they had to make it to Milford to catch a cruise, anxiety levels would go up, he said.

"If you're not accustomed to the road or New Zealand driving, you need to allow time [to get there]," he said.

Southland area commander Inspector Joel Lamb said the road was now partially open and efforts would be made to fully reopen the route after the vehicles have been recovered.