Japan's northwest coast around Niigata prefecture was hit by an earthquake with a preliminary magnitude of 6.8 on Tuesday, with shaking strong enough to damage buildings and prompting a 0.2-1.0 metre tsunami warning. There were no immediate reports of damage, although areas hardest hit by the quake could not be contacted by telephone.
Tokyo Electric Power Co's Kashiwazaki-Kariwa nuclear plant was not affected by the quake, which hit 85 km ( 53 miles) northeast off the coast, with all of its seven reactors already shut down, NHK said. The quake struck at 10.22 p.m. local time (1322 GMT Thursday) at a depth of 10 kilometres. The U.S. Geological Survey (USGS) put the magnitude of the quake at 6.5.