World

Powerful but deep earthquake strikes off Japan; no tsunami warning

  • Japanese soccer fans react to a strong earthquake as they watch a J-League soccer match between the Shonan Bellmare and the Sanfrecce Hiroshima at BMW Stadium in Hiratsuka, southwest of Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Munehide Someya/Kyodo News via AP)

    Japanese soccer fans react to a strong earthquake as they watch a J-League soccer match between the Shonan Bellmare and the Sanfrecce Hiroshima at BMW Stadium in Hiratsuka, southwest of Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Munehide Someya/Kyodo News via AP)  (The Associated Press)

  • A large screen displays an earthquake alert to soccer fans as a strong earthquake jolts Shonan BMW Stadium where a J-League soccer match between the Shonan Bellmare and the Sanfrecce Hiroshima is being held in Hiratsuka, southwest of Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Yohei Nishimura/Kyodo News via AP)

    A large screen displays an earthquake alert to soccer fans as a strong earthquake jolts Shonan BMW Stadium where a J-League soccer match between the Shonan Bellmare and the Sanfrecce Hiroshima is being held in Hiratsuka, southwest of Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Yohei Nishimura/Kyodo News via AP)  (The Associated Press)

  • A Japanese kendo player looks up the ceiling as a strong earthquake jolts Nippon Budokan martial arts hall during an awarding ceremony for the World Kendo Championships in Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Meika Fujio/Kyodo News via AP)

    A Japanese kendo player looks up the ceiling as a strong earthquake jolts Nippon Budokan martial arts hall during an awarding ceremony for the World Kendo Championships in Tokyo Saturday, May 30, 2015. A powerful and extremely deep earthquake struck a group of remote Japanese islands and shook Tokyo on Saturday, but officials said there was no danger of a tsunami, and no injuries or damage were immediately reported. (Meika Fujio/Kyodo News via AP)  (The Associated Press)

A powerful but extremely deep earthquake has struck off Japan's Ogasawara islands, but officials say there is no danger of a tsunami.

Japan's Meteorological Agency says the offshore earthquake struck Saturday at 8:24 p.m. at a depth of 590 kilometers (370 miles). The U.S. Geological Survey says the quake had a magnitude of 7.8 and a depth of 678 kilometers (421 miles).

Public broadcaster NHK said there were no immediate reports of injuries or damage.

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

The Ogasawara islands are about 1,000 kilometers (620 miles) south of Tokyo.