Police in central Japan plan to launch a search operation on Monday morning for two foreigners who survivors say remain unconscious at the site of an avalanche in Nagano Prefecture.

Police received a call from a foreign national on Sunday afternoon that the avalanche hit back country terrain off regular skiing courses of the Tsugaike Mountain Resort in Otari Village.

The disaster area is on the eastern slope of the Tenguhara area, some 2,100 meters above sea level on Mount Hakuba-Norikura.

Police and firefighters say 10 or more foreigners from at least three groups were in the location when the avalanche struck. They add that at least five of them were caught by the snow slide.

Most members of the groups climbed down the mountain on their own. One of them was transported to a hospital for treatment of a shoulder pain.