The eruption began after midnight on Sunday morning, causing the ground to rumble and windows to shake in central Gunma and northern Nagano prefecture, where Asama straddles the border.

Residents in cities and villages nearby were warned to be alert for flying rocks and ash, while children were advised to wear masks to school to prevent them from inhaling the fine particles of volcanic debris.

Mount Asama is one of Japan’s most active volcanoes. Its most powerful eruption of the last two decades occurred on Sept. 1, 2004, when it spewed hot rock and sent ash raining down as far as 125 miles (200 km) away. The ash caused extensive losses to farmers at that time.

A huge blast from the mountain in 1783 killed about 1,500 people and caused extensive damage.

Off southern Japan’s Kyushu Island, Mount Sakurajima produced seven minor eruptions as well on Sunday, throwing up rocks more than a mile into the air, according to the Japan Meteorological Agency.

The Fukuoka District Meteorological Observatory raised the alert level because it said it expected debris could reach surrounding areas as activity within Sakurajima increased.

Photo: Land, Infrastructure and Transport Ministry
Video of latsest Mount Asama eruption