The rescue helicopter team called in to airlift nine patients after a jet boat crashed on a remote part of Queenstown's Shotover River had to make two trips to get all the patients to hospital.
Ten people were onboard the boat when it crashed into rocks while riding the Shotover River just after 10am.
The group were roughly halfway through the trip down the river when the incident occurred.
Several passengers were part of a group of tourists from Thailand. Two others were Canadian tourists - one, a middle-aged woman, was suspected to have a broken leg.
Otago Rescue Helicopter Trust's chief pilot Graham Gale said his team were called in to transport patients from the spot, which was tricky to access.
"There is no road - there is no road access to where we picked them up from," he said.
The team made two trips transporting patients to Lakes District Hospital. The Canadian woman with the injured leg was transferred to Dunedin Hospital shortly after.
Gale had not assisted in the rescue but said the patients were agitated.
"You're in an incident like that ... everyone is always distressed to a certain level when they're involved.
"We're quite focused on doing what we do - we go in there and we do the business, get them out, and get them away to hospital."
Skippers Canyon Jet marketing manager Gavin Larsen said the company's commercial boat rides would be suspended until an investigation is complete and when the company had determined what had happened.
Larsen said the investigation could start tomorrow.
A witness at the scene said the accident appeared to have happened about 200 metres downstream of the Skippers Canyon suspension bridge.
"It looks like it was a substantial accident."
The witness said it was a beautiful, hot day in Queenstown, with a bit of cloud overhead.
Queenstown Lakes District Council mayor Jim Boult said jet boat rides on the Shotover River were immensely popular with tourists.
"Jet boating is synonymous with Queenstown. I couldn't tell you exact numbers but I'd imagine an excess of a couple of hundred thousand people a year would undertake one of the activities on the river."
Boult said his first concern was for those involved.
"I'm sure the appropriate bodies are looking after the welfare of those people.
"The second concern is to ensure the accident is thoroughly investigated - I'm sure we'll run a very thorough investigation into that."
The Transport Accident Investigation Commission had been notified of the accident, as had Maritime New Zealand.
The Transport Accident Investigation Commission confirmed it had opened an investigation into the accident.