Strong Quake Shakes Japan

A strong earthquake shook northern Japan late Monday night, but there were no immediate reports of damage or injuries.

Japan's Meteorological Agency said the magnitude-7.0 quake, which struck off the coast of Japan's northernmost main island of Hokkaido at 11:15 p.m., was centered about 31 miles beneath the ocean floor.

The agency quickly issued a tsunami warning for the eastern shores of Hokkaido's Pacific coastal area but later lifted it after determining that any waves were unlikely to cause damage. Tsunami are potentially dangerous waves triggered by seismic or volcanic activity.

Public broadcaster NHK showed video of an office in Nemuro city, about 556 miles northwest of Tokyo, shaking for about 30 seconds.

In nearby Akkeshi, where the temblor hit hardest, some residents reported items falling off shelves, said town official Masayasu Tanabe.

Train service in eastern Hokkaido was suspended for safety inspections, and homes in some areas lost power, NHK said.

Monday's quake was the second sizable one to strike Hokkaido in the past week. On Nov. 29, a powerful earthquake with a preliminary magnitude of 7.1 struck Hokkaido injuring 24 people, swaying buildings and triggering a small tsunami wave that reached the shore.

A magnitude-7 can cause widespread, heavy damage in a densely populated area. But Monday's temblor was centered deep beneath the earth's surface, damping much of its power.

Japan is one of the world's most earthquake-prone nations.