Magnitude 6.4 earthquake strikes southeast of Tokyo

A strong undersea earthquake with a magnitude of 6.4 has struck southeast of Tokyo, the US Geological Survey (USGS) said.

There was no tsunami warning issued by the Pacific Tsunami Warning Centre in Hawaii.

Japan's weather agency said there could be slight changes in the sea level but no damage to Japan.

The quake's epicentre was 226km southeast of the Japanese capital at a shallow depth of 10km.