A powerful offshore earthquake rattled northern Japan late Monday, triggering tsunami warnings, injuring dozens, and prompting authorities to issue an unprecedented advisory for a possible "megaquake" in the days ahead.
The magnitude-7.5 quake struck at 11:15 p.m. local time off the Sanriku coast near Aomori Prefecture, according to the Japan Meteorological Agency. Shaking reached an "upper 6" on Japan's seven-level intensity scale in parts of Aomori, strong enough to make standing impossible and send furniture crashing across rooms.
