Just ten minutes after the earthquake, the Pacific Tsunami Warning System, coordinated by UNESCO, issued an initial warning covering the areas most at risk, particularly the Russian and Japanese coasts. This warning was then relayed by national centers and enabled the immediate implementation of evacuation plans in several countries.

Alerts for a potential tsunami were issued for coastlines in North America, Hawaii, Russia and Japan after a powerful 8.8-magnitude earthquake struck in the North Pacific Ocean off Russia’s northern Pacific coast, according to the U.S. Tsunami Warning System, which is part of the National Weather Service.