In Hawaii, the governor calmly told residents to head for higher ground and warned of heavy damage. In Japan, where residents are still scarred from a 2011 tsunami and nuclear disaster, a normally staid TV newscaster screamed at his viewers: "Do not be glued to the screen. Evacuate now!"

A wave of dread moved at lightning speed across the Pacific Ocean after one of the biggest earthquakes ever recorded hit Russia’s Far East early on July 30, churning up instant fears of a tsunami with the power to devastate communities from Alaska to California and as far away as French Polynesia and Chile.

Then, hours later, after thousands braved gridlocked evacuation routes and displaced residents bedded down on hard shelter floors, came the relief. "So far, we have not seen a wave of consequence, which is a great relief to us," Hawaii Gov. Josh Green told reporters as he lifted some evacuation orders.

More: Tsunami evacuation orders lifted in Hawaii, threat to West Coast eases

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