A north Canterbury couple has been formally identified as the victims of a helicopter crash near Kaikōura on Tuesday.
Andrew Hamish Davidson, 60, and his wife Lin Chen, 39, were killed in the chopper crash at the Kekerengu River mouth about 12:40pm.
Three other people, two reportedly their children, were seriously injured and airlifted to Wellington Hospital.
Stuff reports that Davidson purchased the helicopter two months ago and was out for a flight with his family when the crash happened.
"This was an incredible tragedy," police said in a statement, adding they were supporting the victim's family and friends.
"The family of the deceased have asked for privacy at this time."
Speaking to Magic Talk Breakfast on Wednesday, eyewitness Ian Mehrtens said one of the children was asking, "is my mum okay"?
"What can you say? I said, 'yeah she's fine' but she wasn't," Mehrtens told host Ryan Bridge.
A local bed and breakfast owner, Mehrtens was one of the first people to arrive at the scene. He said there were "quiet a few" members of the public there to assist.
"It was a really good team effort to get them out."
Mehrtens said the scene was horrific.
"It just fell out of the sky," he told Magic Talk.
"The helicopter was on its side - the door was smashed away and we had to get into them, undo their seatbelts and then lift them out."
In total, Mehrtens assisted four people from the chopper.
"It took three or four of us to lift one person at out one time.
"Being on its side it was so awkward because you had landing gear and stuff like that in the way.
"[It was] so busted up - everything you stood on just about gave way on you all the time."
The area was popular for scenic chopper flights, he said.
"[It's] such a beautiful place."
The Transport Accident Investigation Authority (TAIC) arrived at the scene on Wednesday.
"Their initial work will include inspecting the wreckage, mapping the site, and talking with witnesses," TAIC incidents chief investigator Harald Hendel said.
"Further evidence-gathering in coming weeks and months will likely include examining the helicopter's components, seeking any recorded data from the helicopter's electronics, and obtaining maintenance records."
Witnesses on Tuesday described seeing the helicopter spinning before it fell from the sky.
"I just saw it go down, went down, there were no explosions or whatnot but it just happened, out of the blue," one resident told Newshub.
The TAIC says it will publish a report on the causes and circumstances of the crash, and what can be done to avoid a similar accident happening again.