About 650 residents were ordered to evacuate Tuesday as a forest fire engulfed part of a mountain on an island in the Seto Inland Sea.

Some 170 firefighters and helicopters from nearby prefectures, as well as Self-Defense Forces units in the area, have been mobilized to fight the blaze on Naoshima Island in Kagawa Prefecture, according to police, prefectural government and other sources.

The fire was first spotted at about 4:30 a.m. on the south slope of 118-meter Mount Seto. It continued to spread, driven by strong winds. The prefectural government said no injuries have been reported.