A two-week Army exercise has been suspended after an SAS trooper died following a training accident in Auckland.
The trooper was taken by helicopter on Wednesday night to Auckland City Hospital, where he was later pronounced dead, the New Zealand Defence Force said in a statement.
Police are investigating what happened on behalf of the coroner and the Defence Force would hold a Court of Inquiry.
"No further details will be released while the process of informing the soldier's wider family is taking place," the statement said.
Deputy Prime Minister Winston Peters confirmed the two-week exercise, which also involved the United States Army, had been suspended as a result of the accident.
He said the media's questions around whether NZDF personnel were put through too rigorous training were better answered by experts.
Peters refused to speculate on the accident, but said any death in the armed forces was of "serious concern".
He passed his condolences onto the man's family.
Counties Manukau Police Detective Senior Sergeant Malcolm Hassall said the trooper died during training at Ardmore.
The SAS has a purpose-built training facility in the south Auckland suburb.
It is essentially a 360-degree live firing range with special features to simulate real-life situations and locations such as aircraft fuselages, ship's bridges and public transport.
Work Safe was also advised of the incident. A spokeswoman said it was making inquiries.
Prime Minister Jacinda Ardern said an investigation would take place to find out what happened.
"We need to do all we can and protect all workers in their workforce," she said.
"Right now my condolences go to the family." A witness, who did not want to be named, said she saw helicopters at Auckland Domain, with an ambulance that appeared to be on standby.
It is unclear whether the gathering was related to the incident at Ardmore.
A St John spokeswoman said it had an ambulance on standby but it was not required for incidents at Ardmore or the Auckland Domain.
The fatality is the second to occur during military training in Auckland this year.
In March, 23-year-old Zachary Yarwood died at the Devonport Naval Base after an advanced diver training session went wrong.
THE ARMY EXERCISE
Wednesday night's training marked the beginning of a two-week New Zealand Army counter-terrorism exercise, run in conjunction with a United States Army Aviation Regiment.
The exercise was planned in 2018 and was meant to be taking place in areas of Auckland, Northland and Waiouru, which was once the army's largest base, until May 23.
The New Zealand Defence Force said the exercise was not in relation to the Christchurch mosque shootings on March 15.
The exercise also involved a large number of soldiers and airmen, as well as Black Hawk and NH90 helicopters.
Its aim was to "practise counter-terrorism integration techniques between the two countries", an NZDF spokeswoman said.
It was originally to involve helicopters flying in the north-west suburb of Whenuapai, south Auckland's Papakura and central Auckland, as well as gunfire activities at Kaipara Air Weapons Range in Northland.
Reports of helicopters flying low over the North Shore suburb of Torbay on Wednesday night were unrelated, a police spokeswoman confirmed.
"[Police] Eagle was used in Torbay last night after a driver failed to stop for police about 8.10pm.
"The vehicle was dumped near Awaruku reserve and the occupants fled on foot, and were not able to be located."
WHAT EXERCISES HAS THE ARMY DONE IN THE PAST?
In 2018, the New Zealand army spent a month on a training exercise in Nelson.
The exercise took place in Nelson's CBD and its surrounding suburbs from February 19 to March 23.
The exercise involved moving military vehicles and soldiers with weapons on main and rural roadways as well as local buildings during the day and night.
Military personnel also had lectures and workshops during the exercise programme.
The exercise occurred after the Southern Katipo military exercise which involved 3000 people from 13 countries in scenario-based training around the top of the South Island.
Southern Katipo is New Zealand's largest military exercise and held every two years in different parts of the country.
In 2017, the Southern Katipo exercise was carried out around the Marlborough, Kaikoura, Tasman and Buller regions.
The scenario for the exercise was that the area was the troubled Becara region, suffering from political instability and unrest. New Zealand was requested to assemble and lead an intervention force comprising a coalition of Pacific Island forum member states.
Soldiers from Tonga, Papua New Guinea, Fiji, Brunei, Malaysia and Timor-Leste took part in the exercise alongside New Zealand.
Small contingents from Australia, Canada, United States of America, France and Britain were also involved.
During an exercise in January 2013, a grenade started a 50-hectare scrub fire on a hot, dry day in West Melton, Canterbury, and the army had to apologise to residents.
An army exercise with high explosives had been planned in March at West Melton but NZDF said it had been suspended "in the wake of the Christchurch mosque shootings".