The eruption started on a smaller scale around March 1, but now Shinmoedake is spewing enough ash from its peak to cause air traffic issues in the area.
The volcano is located in a rural area around 616 miles from Tokyo on Japan’s southernmost island of Kyushu.
The volcano was famously featured in the 1967 James Bond film ‘You Only Live Twice’, where smoke was seen pluming from the crater after an eruption.
Incredible footage captured by the Japan Meteorological Agency shows smoke and ash bellowing from the crater of Shinmoedake as the eruption escalates.
It is the first time in seven years such explosive eruption activity has been felt in the area, according to JMA.
The activity has prompted officials to issue a restriction to warn people from accessing the entire mountain.
The danger zone around the volcano may be expanded on Thursday to a 3km radius around the crater.
A JMA official said: “The mountain has been erupting for a while, but this is the strongest day yet.
“This will go on for a while.”
The JMA has maintained its warning at level 3 out of a maximum of five following the eruption, urging people to avoid the area because of flying volcanic rocks.
In January, a member of Japan’s self-defence forces died and about a dozen skiers were injured after a volcanic eruption at a mountain resort in central Japan.
Some 40 flights were cancelled in the region on Tuesday after the Shinmoedake eruption worsened.