TOKYO A strong earthquake with a preliminary magnitude of 6.7 jolted a wide area of eastern Japan early on Thursday, including Tokyo, the Japan Meteorological Agency said.
There were no immediate reports of damage, although television pictures showed computer screens rocking and hanging objects swinging in a newsroom at public broadcaster NHK.
The quake, at 1:45 a.m. (12:45 p.m. EDT Wednesday), was centered around 160 km (100 miles) east of Tokyo, around 40 km (25 miles) below sea level in the Pacific Ocean, the agency and its U.S. equivalent, the U.S. Geological Survey, said.
"There have been no reports of damage so far. There was radical shaking from side to side," Yoshihisa Wakui, an official in Motegi, around 80 km (50 miles) north of Tokyo, told NHK.
"I was taking a nap, but then there was such a big shaking."
Motegi, in Tochigi prefecture north of Tokyo, was among areas to feel the quake most strongly, with the agency putting the effect there at five on the Japanese quake intensity scale of seven.
The tremor was one of three of magnitude 6 or greater to hit the same area in less than 45 minutes but NHK said there was no damage to nuclear facilities in Ibaraki and neighbouring Fukushima prefectures north of Tokyo, among areas where the quake was felt most strongly, and train services were not affected.neighboring
No tsunami damage was expected from the quake, but there may be slight sea level changes, the Japanese Meteorological Agency said on its website (www.jma.go.jp).
Earthquakes are common in Japan, one of the world's most seismically active areas. The country accounts for about 20 percent of the world's earthquakes of magnitude 6 or greater.
In October 2004, an earthquake with a magnitude of 6.8 struck the Niigata region in northern Japan, killing 65 people and injuring more than 3,000.
That was the deadliest quake since a magnitude 7.3 tremor hit the city of Kobe in 1995, killing more than 6,400.
(Reporting by Teruaki Ueno and Hugh Lawson; Editing by Rodney Joyce)