A strong earthquake jolted north-eastern Japan today and a tsunami warning has been issued.

Buildings in Tokyo swayed for several minutes.

The Japan Meteorological Agency said the earthquake, with a preliminary magnitude of 7.3, struck in the Pacific Ocean off the coast of Miyagi prefecture at 8.18am UK time.

The epicentre was 6.2 miles beneath the seabed.

The warning said the tsunami could be as high as six feet.