A 6.9 magnitude earthquake shook the northeastern coast of Japan on June 25, but no tsunami warnings were issued.
So far, no immediate casualties have been recorded and no abnormalities have been detected at nuclear facilities, according to authorities.
Cabinet Secretary Minoru Kihara told reporters that the Japanese government has established an emergency team to gather information about the earthquake in the Tohoku region and is ready for disaster relief operations.
The Japan Meteorological Agency said that the epicenter of the earthquake was at a depth of about 50km, off the coast of Iwate prefecture, and no tsunami damage was forecast, except for slight changes in sea level.
On Japan's earthquake magnitude scale from 0 to 7, the most severely affected area is Aomori Prefecture at 6 plus, a level defined as making it impossible for humans to stand or move without crawling.
Tohoku Power Company said it did not detect any abnormalities at the suspended Onagawa and Higashidori nuclear power plants. The Nuclear Regulatory Authority said that nearby nuclear facilities of Tokyo Power Company and other companies also did not record any abnormalities.
East Japan Railway Company said it has temporarily suspended some trains, including the Tohoku Shinkansen high-speed train service, after the earthquake. High-speed trains in Aomori have been closed for inspection.
Earthquakes are a common occurrence in Japan, one of the regions with the strongest seismic activity in the world. Japan accounts for about one-fifth (1/5) of earthquakes with magnitudes of 6 degrees or more globally.
In March 2011, the northeastern coast of this country suffered a magnitude 9 earthquake, the strongest earthquake ever recorded in Japan, along with a giant tsunami. These events caused the world's worst nuclear crisis since the Chernobyl disaster a quarter of a century earlier.
