A 6.8-magnitude earthquake occurred off the coast of Hokkaido in northern Japan on Saturday, but the Japan Meteorological Agency did not issue a tsunami warning.
Japanese researchers yesterday called on authorities to prepare for a catastrophic 'mega-earthquake' after a 7.1-magnitude quake on Thursday resulted in eight injuries in the south of the country. Meanwhile, Japanese authorities today advised citizens not to hastily stockpile everyday goods due to increasing worries about a possible super-earthquake.
