An hour ago, Reuters reported an event as a 6.8 magnitude:
A strong earthquake with a preliminary magnitude of 6.8 jolted northeastern Japan off Fukushima prefecture on Friday, the Japan Meteorological Agency said, although no damage was reported and a tsunami advisory for the area was lifted after no waves were sighted.
Washington Post reports a 6.5 and says this is one of the biggest in a month and that Japan's northeastern coast has been the site of more than 1,000 aftershocks of magnitude 4.0 or higher since March.
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