Dozens of residents have been evacuated from their homes on remote islands in southern Japan that have experienced nearly 1,600 earthquakes in recent weeks, a local municipal government official said today.

On Akuseiki island, which is the hardest hit, no major property damage has been reported even after a 5.1-magnitude earthquake struck overnight, said Mayor Genisiro Kubo, whose headquarters is on another island.

But earthquakes that have been going on uninterrupted for more than two weeks have caused considerable stress for local residents, many of whom are suffering from lack of sleep.

Of the 89 residents of Akuseki, 44 evacuated to the regional center of Kagoshima yesterday, Sunday, and 15 others also fled a neighboring island, Kubo explained at a press conference.

The island of Akuseki, part of the Tokara island cluster, which lies south of the Kyushu region, has experienced more than 1,600 earthquakes since June 21.

The municipality, which consists of seven inhabited islands and five uninhabited ones, is about an 11-hour ferry ride from Kagoshima.

Experts believe the phenomenon may be caused by an undersea volcano and magma flows, and specify that it is impossible for them to predict how long the earthquakes will last.

“We can’t predict what could happen. We don’t know when it will end,”Kumbo told reporters.

The Tokara island cluster had experienced a similar period of intense seismic activity in September 2023, when 346 earthquakes were recorded, according to the Japan Meteorological Agency (JMA).

Japan is located where four major tectonic plates meet, at the heart of the “ring of fire” in the Pacific, making it one of the most earthquake-prone countries in the world.

The archipelago of about 125 million people records about 1,500 earthquakes a year, or about 18% of the world’s earthquakes.

Japanese authorities are particularly concerned about a large earthquake on the Nankai undersea fault of about 800 kilometers (1,000 miles) along the Pacific coast. Such earthquakes occur every 100 to 200 years or so, with the last one recorded in 1946.

Japan last Tuesday unveiled a new updated disaster preparedness plan, estimating that much remains to be done to limit the impact of a potential “megaquake” that could cause up to 300,000 deaths in the archipelago.