The earthquake had a preliminary magnitude of 7.3, the US Geological Survey said, adding that there was no risk of a widespread tsunami. That was revised from an earlier estimate of 7.4.
A one-metre-high tsunami has hit Japan's northeast coast was recorded in Ishinomaki, a city in Miyagi prefecture that was badly hit by the tsunami of March 2011, which killed thousands.
People crowd at Sendai railway station in Sendai, Miyagi Prefecture, after trains were halted following a strong earthquake struck off the coast of northeastern Japan.
