Buildings in Tokyo shook Tuesday as a powerful quake hits Japan, AFP reporters in the city said.
The Japan Meteorological Agency said the epicentre was believed to be in the south of Ibaraki prefecture, an area to the east of Tokyo, and was located around 50 kilometres (30 miles) below the surface.
They put the initial magnitude at 5.6, and said there was no immediate risk of a tsunami from the quake, the effects of which could be felt in buildings for more than a minute after the initial shaking began.
Japan is hit by around a fifth of the world's powerful quakes every year and sits at the conjunction of several tectonic plates.