A magnitude 6.6 earthquake hit southwestern Japan late Monday, prompting tsunami advisories and evacuation warnings in coastal areas, according to Japan’s Meteorological Agency (JMA). The alerts were lifted a few hours later.
Initially estimated at magnitude 6.9, the quake’s strength was revised downward twice—first to 6.7 and then to 6.6. It struck at 9:19 p.m. local time at a depth of 18.6 miles, with the epicenter in Miyazaki prefecture on the southwestern island of Kyushu.
One person suffered minor injuries in Kyushu, falling down stairs during the quake, NHK TV reported. Train services were suspended at Miyazaki Station, leaving passengers stranded.
A small tsunami, estimated at 8 inches high, was recorded at Miyazaki Port, significantly lower than the initial advisory estimate of 3.2 feet.
Tsunami warnings were issued for Miyazaki and neighboring Kochi prefecture on Shikoku island. These were lifted shortly before midnight, though the JMA urged the public to stay away from coastal waters, warning that aftershocks and secondary hazards, such as landslides, could occur in the coming days.
“There is no tsunami threat from this earthquake” for the United States, the U.S. Geological Survey confirmed after revising its own estimate to 6.6.
Despite the shaking, infrastructure in Kyushu appeared largely unaffected, with NHK footage showing functioning traffic and streetlights. Nuclear plant monitoring stations in the region also reported no irregularities.
Japan, located along the seismically active “Ring of Fire,” frequently experiences earthquakes. The latest tremor prompted experts to assess its connection to the Nankai Trough, a region known for producing major quakes. No extraordinary measures were deemed necessary for now.
The Nankai Trough has a history of devastating earthquakes, including one in 1946 that killed over 1,300 people. The memory of the 2011 Tohoku disaster—a 9.0-magnitude undersea quake that caused a catastrophic tsunami and the Fukushima nuclear meltdown—continues to shape Japan’s disaster preparedness strategies.
The country enforces strict building codes and conducts regular emergency drills to mitigate earthquake risks. However, with its long history of seismic disasters, Japan remains vigilant about the potential for future large-scale quakes.
Agence France-Presse contributed to this report.