More than 100 people have been injured but no fatalities are reported after a powerful earthquake early Thursday morning local time, in northeastern Japan. VOA correspondent Steve Herman reports from Tokyo.

Japan dispatched troops and military aircraft to survey damage from a tremor which disrupted transportation services in a sparsely populated area of the country. Hundreds of people were trapped in trains which stopped running and some highways were blocked by falling boulders.

Most of those injured apparently fell or were hit by shattering glass.

The earthquake caused power blackouts in the Tohoku region.

Authorities report none of the nuclear power plants in the area were damaged and all are operating normally.

The quake awakened people are far away as the capital, Tokyo, 550 kilometers southwest of the temblor's epicenter.

Japan Meteorological Agency official Takashi Yokota say the quake measured six-point-eight on the Richter scale and was focused more than 100 kilometers underground in a coastal area.

The seismologist says aftershocks are a worry but because the tremor originated so deep below the surface, no major subsequent tremors are expected. The agency warns the main fear is the threat of landslides because heavy rain is expected later in the day.

Japan's government says Prime Minister Yasuo Fukuda has established an emergency task force at his office to assess the damage and assist victims.

The island nation, located where several tectonic plates meet, is one of the world's most earthquake-prone countries.