Mount Shindake erupts in Japan

Authorities have issued an evacuation order for the small Southern island

A volcano has erupted on a small island in Southern Japan today, prompting an evacuation order from authorities.

No injuries have been reported since the 10am eruption, which sent a dense pyroclastic flow of rock and hot gases seaward.

The Japan Meteorological Agency raised the volcano alert to five for Kuchinoerabu island, where Shindake is located. Shindake also erupted in August last year for the first time since 1980.

Chief government spokesman Yoshihide Suga said that the coast guard had dispatched a ship to help evacuate residents and a military helicopter has been sent to survey the island and assess damage.

"There was a really loud, 'dong' sound of an explosion, and then black smoke rose, darkening the sky," he told the national broadcaster NHK. "It smelled of sulphur."

Smoke spews from the erupting crater of Mount Shindake on Kuchinoerabujima island, Kagoshima Prefecture (Reuters)

Hayashi said a few people on the island were still unaccounted for. One person, who lives in an area that is generally off-limits, was to be evacuated by boat as he could not travel safely to the shelter by land.

"The skies here are blue, but smoke is still rising to the west," he said.

Schoolchildren at Nagata Elementary School on Yakushima Island looking towards volcanic ash rising from Mt. Shindake on Kuchinoerabu Island (EPA)

Kuchinoerabu is 50 miles southwest of the main southern island of Kyushu, and is a heavily forested mountainous national park island, supported mainly by tourism and fishing.