AN AUSTRALIAN FAMILY who went missing at a Japanese ski resort have been rescued after sending out a social media SOS, and spending a chilly night in a snow cave, police and reports said today.

The unnamed mother and her three sons were found on the mountain shortly after 9am local time (11pm Monday here), a police spokesman told AFP.

“We understand they were found uninjured,” the spokesman added.

The search was on for the foursome – a mother in her fifties, two adult sons, and a younger boy – after they did not return from skiing last night at Nozawa Onsen in Nagano prefecture, some 200 kilometres north of Tokyo.

The resort, known for deep powder snow and hot springs, is particularly popular with Australian skiers and snowboarders.

“Good News out of Nozawa Onsen! The missing family has just been found up the top of the mountain!” a local tour company said on its Facebook page.

“Have just gotten off the phone with the head of Nozawa Ski Patrol and all members are fine. Everyone is very relieved to hear,” Nozawa Holidays said.

Japanese reports said the group sent a message through social media to let friends and relatives know they were lost and needed help.

The group reportedly dug a hole in the snow to keep warm as the mercury dropped well below zero degrees celsius.

- © AFP 2017

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