TOKYO (AP) -- Japan's Meteorological Agency says a magnitude 7 earthquake has hit northern Japan, and a tsunami warning has been issued.

The quake hit Thursday morning off the eastern coast of Hokkaido, Japan's northernmost island.

Authorities say there are no immediate reports of injuries or damage.

However, a warning has been issued for a 20-inch tsunami along the eastern coast of Hokkaido and the northeastern coast of Japan's main island of Honshu.

The U.S. Geological Survey gives the quake a preliminary magnitude of 7.2.

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