An earthquake measuring 6.8 on the Richter scale occurred in northern Japan early on Wednesday, injuring more than a dozen people.
At least 43 people in the city of Hachinohe were taken to hospital afterwards.
The Japan Meteorological Agency said the quake occurred at 0.26am in Iwate prefecture. It was centred 120km underground.
The quake was strong enough to shake buildings in the capital, some 500km to the south.
It was near the epicentre of an earthquake that measured 7.2 on the Richter scale on 14 June, in which at least 13 people were killed. Ten others were missing.