Japan issues Nankai Trough 'megaquake' warning after 7.1-magnitude temblor

Japan issued a tsunami warning Thursday after a 7.1-magnitude earthquake struck off the southern island of Kyushu.

TOKYO — Japan issued its first warning Thursday about the possibility of a long-feared "megaquake" after a powerful 7.1-magnitude temblor struck off its southern coast, sparking a tsunami advisory but no immediate reports of serious damage or injuries.

Google MapsThe earthquake occurred off the coast of Miyazaki Prefecture on the main island of Kyushu at 4:42 p.m. local time (3:42 a.m. ET), at a depth of about 18 miles, according to the Japan Meteorological Agency.

Three people were reported injured, Japan's Chief Cabinet Secretary Yoshimasa Hayashi said, although he added that there had been no blackouts or damage to the water or communications systems reported in the region. Police in Miyazaki Prefecture said there had been 10 reports of damage. Hayashi urged residents to stay away from the coastline.

Seismologists held an emergency meeting to analyze whether the quake had affected the nearby Nankai Trough — the source of past devastating earthquakes. The meteorological agency ultimately issued what it called a "mega earthquake caution," assessing that the possibility of a large quake was relatively higher than usual but not that one would definitely occur in the near future.

It urged the country's residents to practice increased vigilance for the next week.

https://www.nbcnews.com/news/world/japan-earthquake-tsunami-advisory-rcna165728

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