A Japanese soldier has been killed in an avalanche in central Japan that appears to have been triggered by a volcanic eruption.
At least 14 people have also been injured, several of them critically.
The eruption sent rocks raining down over a kilometre-wide area near Kusatsu in central Japan, say local media.
Mount Kusatsu-Shirane, 150km (93 miles) from Tokyo, erupted on Tuesday but it is not confirmed if that is what triggered the avalanche.
A vent on the side of the volcano appears to have blown out. Video from a CCTV camera shows a large cloud of black ash and rock being thrown down the mountainside, says the BBC's Rupert Wingfield-Hayes in Tokyo.
The eruption is thought to have triggered an avalanche, trapping several skiers on a slope.
Six members of the military, who were conducting an exercise in the area, were among them and had to be rescued. Most of them were injured and one of them later died.
They were members of Japan's Ground Self Defence Force (SDF) and had been doing winter training manoeuvres, according to Defence Minister Itsunori Onodera.
Four people who were riding a gondola at the resort at the time were also among those injured.
One person was initially reported missing in the avalanche, but officials later said that was not the case.
At least 78 skiers are still trapped at a rest house on top of the mountain, according to a local town official.
Japan's Meteorological Agency has warned people not climb the mountain.
Rocks raining down
According to state broadcaster NHK, some of the volcanic debris fell more than 1km (0.6 miles) from the mountain.
"Black smoke rose from the top of the mountain and we were told to evacuate inside 30 minutes later," an eyewitness at the resort told NHK, adding that around 100 people had been evacuated.
The Fire and Disaster Management Agency warned that rocks could be raining down as far as 2km from the peak, Reuters said.
Japan is one of the world's most seismically active nations and closely monitors its volcanoes, reports BBC.