The Japan Meteorological Agency said on Sunday that the alert level was raised to the highest level amid the Sakurajima eruption on the southern island of Kyushu.
NHK reported on Monday that evacuation orders had been issued for a total of 51 people from 33 different families. Out of these, 33 people have evacuated so far.
Kyodo said citing the Japan Meteorological Agency on Monday that the Sakurajima volcano spewed ash over 7,200 feet (2,200 meters) high at around 6:30 local time on Monday (21:30 GMT on Sunday).
There have been no reports of casualties or damages.