More than 60 students and teachers were skiing in the resort just 75 miles north of Tokyo when the avalanche hit.
Rescue authorities say that at least eight students have lost their lives and more than 30 people have been injured.
The Guardian reports that rescue efforts are now being hampered by bad weather and heavy snowfall.
Japan’s Defense Forces have been asked to help with the disaster response as the search continues for victims.
The snow usually tapers off this time of the year which makes it safer for climbing but Japanese meteorologists said that there had been an unusual spike in the snow dept recently – that mixed with the warmer weather created a trigger for the avalanche.
The Nasu Onsen ski resort is a family-friendly complex on the outskirts of Tokyo.
Government officials have released a statement saying the rescue is now a top priority.
