Authorities in Japan have issued a tsunami warning after a strong earthquake shook the sea floor off the country's northeastern coast.

Japan's Meteorological Agency said tsunamis as high as 50 centimeters could reach Japan's Pacific shore.

The quake, which measured 7.2 on the Richter scale, was centered about 315 kilometers east of the Japanese island of Honshu.

There were no immediate reports of injury or damage.

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

Some information for this story provided by AP and Reuters.