Powerful Quake Strikes off Japan; No Tsunami Warning.

A powerful and extremely deep earthquake struck near remote Japanese islands and shook most of the country on Saturday evening, but officials said there was no threat of a tsunami, and no injuries or damage were immediately reported.

The magnitude-8.5 offshore quake struck off the Ogasawara islands at a depth of 590 kilometres (370 miles), Japan's Meteorological Agency said.

The U.S. Geological Survey said the quake had a magnitude of 7.8 and a depth of 678 kilometres (421 miles).

The tremor was powerful enough to rattle most of Japan, from the southern islands of Okinawa to Hokkaido in the north.


Buildings swayed in Tokyo — about 1,000 kilometres (620 miles) north of the Ogasawara islands — and disrupted some train services in the city.

About 400 houses in Saitama prefecture, just north of Tokyo, were without power, according to the Tokyo Electric Power Co.

At Tokyo's Roppongi Hills shopping and business complex, elevators stopped soon after the earthquake struck the area.

NHK said there were no reports of injuries or damage from the quake.

The meteorological agency did not issue a tsunami warning because the quake struck so far beneath the earth's surface.

Deep offshore earthquakes usually do not cause tsunamis, and generally cause less damage than shallow ones.

In March 2011, a magnitude-9.0 earthquake rocked north-eastern Japan, triggering a tsunami that killed more than 18,500 people and ravaged much of the northern Pacific coast. The depth of that quake was just 24 kilometres (15 miles), ac