Residents in northern Japan were urged to stay away from coastal areas Monday afternoon after a preliminary magnitude 7.7 earthquake hit the area and triggered a tsunami warning. Authorities cautioned that waves could reach heights of up to 10 feet, though the warning was later downgraded to an advisory after waves of up of to 2½ feet were reported.
The Cabinet Office and the Japan Meteorological Agency said in the week following the earthquake, the probability of a mega-quake — a magnitude 8.0 or stronger — increased to 1%. While that number remains low, it is 10 times higher than the normal 0.1% chance, according to Reuters.
The quake struck at 4:53 p.m. at a depth of 11 miles off the coast of Sanriku in the Pacific Ocean, as reported by The Associated Press.
This marks the second time in recent months a similar advisory has been issued in the area. A previous warning was issued in December following a 7.5-magnitude earthquake.
Japan’s Fire and Disaster Management Agency has reported one injury so far, according to The Associated Press. Chief Cabinet Secretary Minoru Kihara told reporters there were no immediate reports of deaths or major structural damage, according to Reuters.
Later Monday evening, the U.S. based Pacific Tsunami Warning Center said the tsunami threat “has now passed,” The Associated Press reported.
Japan is one of the world’s most earthquake-prone nations. Located along the “Ring of Fire,” the country accounts for several of the world’s earthquakes of magnitude 6.0 or greater and experiences a tremor roughly every five minutes, according to Reuters.
Impact to the U.S.
The U.S. National Tsunami Warning Center said no tsunami impact was expected for British Columbia or U.S. West Coast states, including Alaska, Washington, Oregon and California, NBC News reported.