"Unconfirmed preliminary reports that we have received indicate that there were seven people involved (in the avalanche) and two are missing," police spokeswoman Maria Linne told AFP.

"A helicopter on the ground was swept away in the avalanche" in Abisko national park, she said, citing the unconfirmed reports.

Linne had no information about the nationalities of those involved.

Swedish media said a group of people were heliskiing in the area when the avalanche occurred.

Both Sweden's and Norway's respective Joint Rescue Coordination Centres told AFP they had dispatched helicopters to the region to assist in the search.