A strong earthquake has rattled northeastern Japan, leaving seven people injured.
No tsunami warning was issued.
The US Geological Survey said the magnitude-6.4 earthquake struck at 3.54am on Sunday (1854 GMT Saturday) off the coast of Fukushima, a region struck by the March 11 massive quake and tsunami. The epicentre was 27 miles below the sea surface.
Plant operator Tokyo Electric Power said the quake caused no further damage to its Fukushima Dai-ichi nuclear power complex, which was crippled by the March disasters.
Seven people in nearby cities were slightly injured.
The March disasters left about 23,000 people dead or missing across Japan's northeast coast and forced 80,000 others to evacuate their homes due to the radiation threat.