The Associated Press
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The center says the evaluation is based on information about the quake and historic tsunami records.
The magnitude-7.3 quake struck at 10:10 a.m. PDT Friday, which was early Saturday morning in Tokyo.
The quake occurred under the ocean off Honshu Island, Japan, about 170 miles off Fukushima.
There were no immediate reports of damage on land. Japanese television images of harbors showed calm waters.
Japanese broadcaster NHK reported that Tokyo Electric Power Co., the operator of the Fukushima plant, ordered workers near the coast to move to higher ground. Japanese news service Kyodo said there were no signs of trouble at the plant.
The tremor was felt in Tokyo, some 300 miles away.
All but two of Japan’s 50 reactors have been offline since the March 2011 magnitude-9.0 earthquake and ensuing tsunami triggered multiple meltdowns and massive radiation leaks at the Fukushima Dai-ichi nuclear power plant, about 160 miles northeast of Tokyo. About 19,000 people were killed.