TOKYO - The Japan Meteorological Agency (JMA) has raised the volcanic alert level for Shinmoedake, a volcano in Japan's southwestern Kyushu region, from Level 2 to Level 3, restricting entry to the mountain as volcanic activity has intensified.

The warning came amid an increase in volcanic earthquakes since Friday and signs of ground deformation indicating mountain expansion.

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Authorities have warned that large volcanic rocks could be ejected within a 4-km radius of the crater. In addition, ashfall and small volcanic rocks may be carried far downwind, and powerful explosions could cause air blasts strong enough to shatter windows.

Due to the alert level upgrade, hiking trails previously restricted within a 2-km radius are now closed within 4 km. Several trails, including those leading to nearby peaks, are now off-limits.

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Residents are advised to avoid the area, follow local government instructions, and take precautions, such as keeping curtains closed to prevent injury from shattered glass.