One of the most powerful earthquakes in modern history shook Russia’s remote east coast Wednesday, sending tsunami waves hurtling across the Pacific Ocean and putting nations from Japan to the United States to Chile on high alert with millions urged to evacuate.

A powerful magnitude 8.8 earthquake off Russia's far-eastern Kamchatka Peninsula Tuesday triggered tsunami waves across the Pacific Ocean. Russia said the shallow quake caused damage in Petropavlovsk-Kamchatsky and elsewhere on the peninsula and flooded the Kuril Islands with waves as high as 19 feet.

An 8.8-magnitude earthquake off Russia's Kamchatka Peninsula shook the Pacific, but its tsunami fizzled. A geologist explains why.