Residents across Japan's Pacific coast rushed to higher ground on Wednesday as tsunami warnings following a massive earthquake off Russia's Far East resurfaced painful memories and lessons from the devastating 2011 earthquake and nuclear disaster.

Tsunami warnings prompted gridlocked traffic as people tried to reach higher elevations in Hawaii, but the threat level was later downgraded.

One of this century’s most powerful earthquakes struck off the coast of Russia and generated tsunami warnings and advisories for a broad section of the Pacific, including Alaska, Hawaii and the U.S. West Coast and as far south as New Zealand.