A strong 6.3-magnitude earthquake struck off northern Kyushu early Friday. Public broadcaster NHK said 17 people were injured. None of the injuries were life-threatening.
The epicenter of the quake -- which struck at 2:06 a.m. -- was located 13 kilometers north of the city of Kunisaki, the U.S. Geological Survey said. The quake hit at a depth of 82 kilometers.
The Japan Meteorological Agency said there was no risk of a tsunami but urged residents to stay on alert.
"We fear the danger of rockfalls and landslides has increased" in areas that felt strong tremors, Yohei Hasegawa, director of the agency's earthquake and tsunami observation division, told a news conference.
The quake, which the Japanese agency measured as having a preliminary magnitude of 6.2, registered a strong intensity in parts of southwestern Shikoku, Honshu and southern Kyushu islands.
There were no abnormalities detected at the Ikata nuclear plant in Ehime Prefecture or at the Shimane plant in Shimane Prefecture.© (c) 2014 AFP