The quake, 200 miles off the coast of Fukushima prefecture, is not likely to cause a catastrophic tsunami, but might affect the stricken nuclear plant that was severely damaged in March 2011 in another trembler and subsequent tsunami.
"Earthquakes of this size sometimes generate local tsunamis that can be destructive along coasts located within a hundred kilometers of the earthquake epicenter," the Pacific Tsunami Warning Center said. "Authorities in the region of the epicenter should be aware of this possibly and take appropriate action."
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