A volcano on an island south of Kagoshima Prefecture erupted early Wednesday, sending large rocks as far as 1 kilometer from the crater, prompting the weather agency to raise its alert level to restrict people's entry to the area surrounding the mountain.
The eruption occurred at the crater of Mount Otake on Suwanose Island at around 12:04 a.m. There were no immediate reports of injuries, according to local authorities, despite there being a small residential area some 4 kilometers from the crater.
Following the eruption, the Meteorological Agency said it had raised the volcanic activity alert level by one notch to 3 on a scale of 5, meaning that people should not approach the mountain.
The agency warned of the potential for big rocks to be hurled into the air within about a 2-kilometer radius of the crater of the mountain in the village of Toshima.
The government set up a liaison office at the Prime Minister's Office to collect information, while the village has a team on watch in the city of Kagoshima.
Suwanose, a volcanic island with a small population of 84 people as of Wednesday, is located about 230 kilometers south of Kagoshima.
The 799-meter volcano has been active, with the alert level raised temporarily due to other eruptions in the past year.
In 1813, a major eruption destroyed nearly all the local houses and forced all residents to evacuate the island for some 70 years, according to the official website of the village of Toshima, which administers the area.