An earthquake with a preliminary magnitude of 5.6 struck off the coast of Fukushima Prefecture early Saturday, the Meteorological Agency said. No tsunami warning was issued.
The 5:08 a.m. temblor, which originated at a depth of about 20 km, registered 4 on the Japanese earthquake intensity scale of 7 in the city of Iwaki.
The quake’s epicenter was 244 km northeast of Tokyo.
Japan sits at the junction of four tectonic plates and experiences a number of relatively violent quakes every year, but rigid building codes and strict enforcement tend to keep damage to a minimum.
In March 2011, however, an offshore mega-quake and tsunami triggered a triple core meltdown at the Fukushima No. 1 power plant — the world’s worst nuclear disaster since Chernobyl. Thousands lost their homes and remain displaced, and parts of the prefecture remain uninhabitable.
On Wednesday, a 6.3-magnitude quake hit 18 km north-northeast of the town of Daigo, but there were no reports of injuries or damage.