The U.S. Pacific Tsunami Warning Center said Monday evening that a magnitude 7.8 earthquake had occurred off the coast of Russia's Kamchatka Peninsula.
"Based on preliminary earthquake parameters... hazardous tsunami waves are possible for coasts located within 300 km (186 miles) of the earthquake epicenter," the center wrote in an official message soon after the quake.
Later Monday evening, a "final" message from the Pacific Tsunami Warning Center assessed that "there is no longer a tsunami threat from this earthquake."
The quake was followed by several aftershocks, including a couple above magnitude 5.0. The earthquake was originally reported as a 7.4 magnitude, but it was subsequently upgraded to 7.8.
On Twitter, the center said soon after the quake that it was not expecting tsunami conditions to impact North American coasts.
—Reuters contributed to this report.