As threat assessments touched off warning sirens across Waikiki, hotels began moving guests mostly to higher floors — a standard protocol known as vertical evacuation.

Japanese officials also downgraded tsunami warnings in the southern half of the country as 1.9 million residents faced evacuation orders along its Pacific coast.

The strongest earthquake of the year erupted off Russia’s Kamchatka region, triggering tsunami warnings for Alaska, Hawaii, Guam, Japan, Russia and the U.S. West Coast.

The earthquake was recorded at about 84 miles east-southeast of of Petropavlovsk-Kamchatsky, Russia, according to the U.S. Geological Survey.