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.

The magnitude 8.8 quake is believed to be the joint sixth-largest on record, though only minor injuries near the epicenter have been reported.

A tsunami has hit coastal areas of Russia’s Kuril Islands and Japan’s large northern island of Hokkaido after an 8.7-magnitude earthquake early on Wednesday. Tsunami warning sirens sounded in Honolulu, Hawaii, where people were told to move to higher ground.