TOKYO - A strong quake with a preliminary magnitude of 5.6 jolted the central Japanese prefecture of Yamanashi and nearby areas on Friday, the weather agency said, with no tsunami warning issued and no abnormality detected in volcanic activity at Mt. Fuji.

The 10:29 p.m. quake, at a depth of around 20 kilometers, measured lower 6 on the Japanese seismic intensity scale of 7 in Fujikawaguchiko, Yamanashi.

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