An earthquake with a preliminary magnitude of 5.8 hit eastern Japan early on Friday, the Japan Meteorological Agency said. The epicentre of the earthquake was off the coast of Fukushima prefecture, where strong tremors were recorded, the agency said, adding that a tsunami warning had not been issued.An earthquake with a preliminary magnitude of 5.8 hit eastern Japan early on Friday, the Japan Meteorological Agency said. The epicentre of the earthquake was off the coast of Fukushima prefecture, where strong tremors were recorded, the agency said, adding that a tsunami warning had not been issued.