There have been no quick stories of harm or accidents in close by cities however residents had been suggested to evacuate.
Japan's Meteorological Company stated Sakurajima volcano erupted about 8.05pm on Sunday (9.05pm AEST), blowing off giant rocks so far as 2.5 kilometres away within the southern prefecture of Kagoshima.
Footage on Japan's NHK public tv confirmed orange flames flashing close to the crater and darkish smoke of ash billowing from the mountaintop excessive up into the evening sky.
"We'll put the folks's lives first and do our utmost to evaluate the state of affairs and reply to any emergency," Deputy Chief Cupboard Secretary Yoshihiko Isozaki instructed reporters.
He known as on residents within the space to pay shut consideration to the newest replace from the native authorities to guard their lives.
The company stated it has raised the eruption alert to the best degree of 5 and about 120 residents in two cities going through the volcano had been suggested to depart their houses.
The company warned of falling volcanic rocks in areas inside three kilometres of the crater and attainable move of lava, ash and searing gasoline inside two kilometres.
Sakurajima, about 1000 kilometres south-west of Tokyo, is among the most energetic volcanos in Japan and has repeatedly erupted.
It was an island however grew to become a peninsula following an eruption in 1914.