Oarfish Warning : 7.3 Earthquake Hits Japan

USGS via EPA

A map of a magnitude-7.3 earthquake which struck 231 miles off the eastern coast of Japan.

TOKYO (AP) — An earthquake of magnitude 7.3 struck early Saturday morning off Japan's east coast, the U.S. Geological Survey said. Japan's emergency agencies declared a tsunami warning for the region that includes the crippled Fukushima nuclear site.

Japan's Meteorological Agency issued a 1-meter (3-foot) tsunami warning for a long stretch of Japan's northeastern coast. It put the magnitude of the quake at 7.1. The U.S. Pacific Tsunami Warning Center did not post warnings for the rest of the Pacific.

There were no immediate reports of damage on land. Japanese television images of harbors showed calm waters.

The quake hit at 2:10 a.m. Saturday Tokyo time (1710 GMT) about 290 kilometers (170 miles) off Fukushima. 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 (480 kilometers) away.