A day after two Australians and two New Zealanders were swept 500 metres (yards) to their deaths by an avalanche, in an area popular with international climbers, the risk level was listed as moderate.

Police senior constable Brent Swanson said there were about 120 people in the park at New Year and the number was expected to increase to about 160 over the next two weeks

"There's still heaps of people in the area," he said, adding the area was avalanche-prone at present, but the risk level was only moderate.

There had been 30-40 centimetres of new snow over the past couple of days, and Mount Cook mountain guide Roy Smith told the Christchurch Press newspaper there had been no heavy snow falls for some time.

"We wouldn't have expected a major avalanche from snow," Smith said.

The Mountain Safety Council's website said the avalanche risk on Aoraki-Mount Cook was low because "recent drops in the freezing level had strengthened up the existing snow pack".

Avalanches usually occur when a snow pack becomes unstable.

TERRA.WIRE