A strong earthquake with a magnitude of 6.8 shook northeastern Japan on Saturday, but there were no immediate reports of serious injuries or abnormalities at nuclear plants and no tsunami warning was issued, Kyodo cited the Japanese authorities as saying. The quake occurred around 10:27 a.m., about 51 kilometers below the sea surface off the coast of Miyagi Prefecture, according to the Japan Meteorological Agency. It registered upper 5 on Japan's seismic intensity scale of 7 in parts of Miyagi and lower 5 in areas including neighboring Fukushima and Iwate prefectures, which were all devastated by a massive quake and tsunami about 10 years ago that subsequently triggered nuclear reactor meltdowns. The weather agency warned that a quake of up to upper 5 on the intensity scale, which would make it difficult for people to walk without holding on to something stable, could occur in the next seven days or so. No irregularities were detected at the Fukushima Daiichi and Daini nuclear power plants, according to Tokyo Electric Power Company Holdings Inc. Officials in Aomori, Fukushima and Iwate said no casualties had been reported.
