Mount Asama near Tokyo, which reportedly erupted for the first time in four years, emits smoke and dust as high as two kilometers into the air.
It also triggered a warning to the public not to approach the mountain.
Mount Asama near Tokyo , located about 140 kilometers northwest of capital city of Japan, erupted overnight and prompted national meteorological agencies to raise the alert level to three out of five points.
The alert level required the public to stay away from the mountain range.
The agency said the eruption would have flown large boulders and hot gas, which could affect an area within four kilometers of the crater.
Meteorological agency said nearby towns are also at risk of being exposed to small rocks and dust, but it depends on the wind conditions.
Meanwhile, an agency official told AFP on Thursday that the explosion was still emitting gas but at normal levels.
“We do not record any increase in activity,” he said.
The last time Mount Asama erupted was in June 2015, but no injuries were reported.
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