A 5.3-magnitude earthquake has hit the Japanese prefecture that is home to the nuclear power plant crippled in the March 2011 quake and tsunami.
The US Geological Survey said the earthquake struck at 2.25am (17.25 GMT) on Friday at a depth of about 22km under the Fukushima prefecture, about 177km northeast of Tokyo.
The Pacific Tsunami Warning Centre did not issue an alert.
The Japanese news agency Kyodo News reported that the plant's operator, Tokyo Electric Power Co (TEPCO), observed no abnormality in radiation or equipment after the earthquake.
Prime Minister Shinzo Abe on Thursday ordered TEPCO to scrap all six reactors at the Fukushima Daiichi plant and concentrate on tackling pressing issues like leaks of radioactive water.
The 2011 disaster caused three reactors to melt and damaged a fuel cooling pool at another.
Officials have acknowledged that radiation-contaminated groundwater has been seeping into the Pacific Ocean since soon after the meltdowns.
The region lies on the "Ring of Fire," an arc of earthquake and volcanic zones that stretches around the Pacific Rim.
About 90 percent of the world's earthquakes occur in the region.