A magnitude 7 earthquake struck the Kamchatka Peninsula region of Russia on Friday, the European-Mediterranean Seismological Centre (EMSC) said.
The quake was at a depth of 140 km (87 miles), EMSC added.
No details of casualties or damage to buildings were given in the initial report.
A magnitude 7 earthquake is a major seismic event. Further official information on possible damage and aftershocks will be important.