A series of spectacular eruptions from a volcano in southern Japan fired columns of ash and smoke thousands of metres in the air early Wednesday, with the cloud delaying some international flights to Tokyo.

The 1,421-metre (4,689-feet) Shinmoedake volcano in the Kirishima range, featured in the 1967 James Bond film "You Only Live Twice", continued the series of deafening blasts which began with the start of its first major eruption for 52 years last week.

After a huge explosion at 5:25 am (2025 GMT), the peak spewed fiery crimson debris and flame into a dark pre-dawn sky, before erupting again at 10:47 am, an official at the Fukuoka District Meteorological Observatory said.

Several inbound international flights to Tokyo's Narita and Haneda airports, including some operated by Hong Kong carrier Cathay Pacific, were delayed Wednesday morning, airline officials said.

However, scheduled flights were expected to return to normal throughout the day, operating above the ash cloud.

Domestic flights and train schedules have been subject to cancellations and sport has also been affected, with three J-League football teams forced to cancel spring training camps in the area, officials said.

On Tuesday the force from a huge blast from the erupting volcano shattered windows up to 12 kilometres (seven miles) away.

The Japan Meteorological Agency widened the zone around the Shinmoedake volcano seen to be at risk from flying debris from three to four kilometres from the peak.

Authorities on Wednesday repeated calls for the public to stay away from the volcano and warned of falling debris in the surrounding area.

Until late Tuesday, the government counted four injuries, including one serious case.

More than 600 residents of the town of Takaharu in Miyazaki prefecture have been forced to evacuate and take shelter in school halls and community centres.

A dome of lava inside the crater, growing as pressure increases from below, has been expanding quickly, prompting concerns it could spill over the rim of the volcano and flow down the sides of the mountain.

The Fukuoka observatory has raised its five-scale warning level on the volcano from two to three, restricting access to the entire mountain.

In April last year the eruption of the Eyjafjoell volcano in Iceland dispersed a vast cloud of ash triggering a huge shutdown of airspace that affected more than 100,000 flights and eight million passengers.