YEREVAN, OCTOBER 21, ARMENPRESS. An earthquake with a preliminary magnitude of 6.6 shook western Japan on Friday, the Japan Meteorological Agency said, adding that a tsunami warning was not issued, reports Reuters.

There were no immediate reports of injuries or major damage and no irregularities at nuclear plants, but media said roughly 40,000 households were without power.

The epicenter of the earthquake was in Tottori prefecture at a depth of 10 km (6 miles), the agency said. The quake occurred at 2:07 p.m. and was followed by a weaker aftershock about 30 minutes later.

Earthquakes are common in Japan, one of the world's most seismically active area. Japan accounts for about 20 percent of the world's earthquakes of magnitude 6 or greater.