A heliskier has been killed following an avalanche in a remote Southern Alps range.

Rescuers were alerted to the avalanche in the Arrowsmith Range about 12.15pm.

Rescue Helicopter pilot Dan McPherson said a group was heliskiing on the mountain when the avalanche struck.

One person was trapped in the snow, he said.

A police spokesperson confirmed one person had died.

"One person was trapped in the avalanche and was in a critical condition when recovered at around 1pm. Tragically they died a short time later."

The rest of the group was accounted for.

McPherson said no one else was injured.

"Details of the deceased cannot be provided until all necessary next of kin notifications have taken place," a police statement said.

A four-person GCH Aviation helicopter crew was sent to the scene and Hato Hone St John sent a helicopter.

Nearby areas were under a considerable avalanche risk advisory, though Mt Arrowsmith was not covered by the NZ Avalanche Advisory.

The NZ Mountain Safety Council (MSC) said it was aware of a possible avalanche but had no further details.