A powerful quake that hit northeast of Japan late on Wednesday has revived public concerns over the country's nuclear energy, in a challenge to those who have argued for plants left idle after the 2011 Fukushima disaster to be restarted.
No abnormalities were reported at any nuclear plants, although authorities had earlier said a fire alarm had been triggered at a turbine building at the Fukushima Daiichi plant that was crippled in the 2011 earthquake and tsunami.
