Japanese authorities on Tuesday issued a tsunami alert after a powerful 7.1-magnitude earthquake struck the country’s southwestern island of Kyushu, triggering power outages affecting thousands of households.
Gatekeepers News reports that the earthquake occurred at 4:27 p.m. local time (0727 GMT) and registered the maximum intensity of seven on Japan’s Shindo seismic scale, according to the Japan Meteorological Agency (JMA).
The agency warned that tsunami waves of up to one metre (about three feet) could reach coastal areas.
Public broadcaster NHK reported that waves of that height may already have been observed.
Authorities said there were no immediate signs of abnormalities at nearby nuclear power plants.
The Nuclear Regulation Authority confirmed that facilities were operating normally, while Kyushu Electric Power said three nuclear reactors in the region remained unaffected despite the earthquake.
However, the utility reported that about 45,000 households and other facilities in Kumamoto Prefecture lost electricity following the tremor.
Around 30 minutes after the earthquake, an NHK reporter wearing a safety helmet described strong aftershocks during a live broadcast.
“Shaking is continuing as I speak. Including myself, there may be some people who feel their hearts racing,” he said.
“When the quake struck, the shaking was so big that I could not stand up. Please be aware of possibility that shaking might continue after this.”
History of Major Earthquakes
Kumamoto Prefecture experienced two devastating earthquakes in 2016—a magnitude 6.5 quake followed two days later by a magnitude 7.3 tremor—that claimed 273 lives and injured more than 2,800 people.
More recently, a magnitude 7.2 earthquake struck northern Japan on June 25 without causing fatalities or significant damage.
Japan is among the world’s most earthquake-prone countries, sitting atop four major tectonic plates along the Pacific “Ring of Fire.” The country experiences hundreds of earthquakes annually and accounts for about 18 per cent of the world’s seismic activity.
While most tremors are relatively minor, their impact depends on their strength, depth and proximity to populated areas.
The country continues to bear the scars of the devastating magnitude 9.0 undersea earthquake and tsunami that struck in 2011, killing or leaving about 18,500 people missing and triggering the Fukushima nuclear disaster.
Earlier this year, on April 20, a magnitude 7.7 earthquake struck northern Japan, injuring at least 10 people and causing buildings in Tokyo to sway. The quake prompted authorities to issue a special advisory warning of an increased risk of earthquakes measuring magnitude 8.0 or higher before the alert was lifted a week later.
