TOKYO, Dec 31 (KUNA) -- A strong earthquake with a preliminary magnitude of 5.4 on the Richter scale struck eastern Japan on Tuesday, the Japan Meteorological Agency said. However, there were no immediate reports of casualties and damage and no tsunami warning was issued for the 10:03 a.m. (0103 GMT) quake.
Focus of the tremor was 10 km underground in northern part of Ibaraki Prefecture, according to the agency.
There were no additional problems with the facilities at the tsunami-crippled Fukushima Daiichi nuclear power plant by the quake, which hit around 80 km south of the plant, its operator Tokyo Electric Power Co. said.
The quake registered lower 5 on the Japanese seismic scale of 7 in the prefecture's Takahagi City, about 150 km north of Tokyo.
The agency defines an intensity of lower 5 as strong enough to make hanging objects swing violently and most unstable ornaments fall.
The Japanese scale measures how much places were shaken on the surface while the Richter scale measures the energy of the quake itself. Japan, located in a zone where the Eurasian, Pacific, Philippine and North American tectonic plates meet and occasionally shift, is hit by 20 percent of the world's earthquakes of magnitude six or greater.
The country was severely damaged by the magnitude 9.0-quake and ensuing tsunami in March 2011 that left nearly 19,000 people dead or missing and damaged the Fukushima nuclear complex. (end) mk.rk KUNA 310940 Dec 13NNNN