Residents of the Tokara Islands in the village of Toshima, Kagoshima Prefecture, began evacuating Friday morning following a powerful magnitude 5.5 earthquake that struck a day earlier, which registered a lower 6 on Japan’s seven-point shindo seismic intensity scale — the highest ever recorded in the region.

No injuries were reported among the 76 residents of Akuseki Island, where the tremor measuring lower 6 on the shindo scale hit at 4:13 p.m. Thursday. However, local officials are offering voluntary evacuation to the city of Kagoshima amid the ongoing earthquakes.

The initial evacuation period is set for about a week but may be extended depending on future seismic activity, Toshima Village Mayor Genichiro Kubo said Thursday during a news conference at the village office in the city of Kagoshima.