NEW ZEALAND: Six Tourists Among Fox Glacier Dead

Two Australian and four British tourists are among the seven people killed in a helicopter crash at a popular South Island tourist site.

Worsening weather and treacherous terrain have halted police efforts to reach the bodies of the victims in the Fox Glacier crash on Saturday.

But police have confirmed the dead include two Australians and four people from the United Kingdom.

The helicopter's pilot was also killed.

The bodies have yet to be formally identified and police are working with embassies to notify the next of kin.

Emergency services were alerted to the crash by a helicopter operator at the West Coast glacier just before 11am on Saturday.

Investigators were on Saturday unable to reach the site of the wreckage, some 700 metres up the glacier.

Inspector John Canning said worsening weather and difficult terrain meant the recovery was slowed on Saturday.

"It's the top of the glacier and it's heavily crevassed, very rough country and it's going to take a lot of care to get the people out of there," he told TV One.

He said the operation had to be taken slowly to avoid danger to rescue teams.

"I'm not going to risk any more lives. We've lost seven."

Police in a statement said they would resume a recovery operation on Sunday.

It is believed the vehicle was a single-engine Eurocopter Squirrel helicopter operated by a service owned by tourism company Alpine Adventures.

The company, like others in the area, provides scenic flights across sights in the area, including the 13-kilometre long glacier.

It is considered among the most accessible glaciers in the world and is popular with tourists.

Weather conditions were reportedly cloudy and raining at the time of the crash.

Four rescue helicopters were dispatched to the scene at 11am, a Rescue Co-ordination Centre spokesman said.

Four crash investigators from the Transport Accident Investigation Commission (TAIC) are expected to begin work on the site on Sunday morning.

The Glacier Country Tourism Group, which represents the bulk of operators in the area, extended its sympathies to all families involved in the accident.

In 2010 nine people were killed when a skydiving plane crashed at the end of the runway of Fox Glacier airport.

Four were tourists and five were locals.

The latest crash comes just weeks after a report into the 2010 accident found there had been faults in the investigation and recommended greater funding for TAIC.

The investigation became the subject of media investigations and intense criticism from some of the victims' families.