An earthquake of magnitude 7.1 struck near the east coast of Russia's Kamchatka region on Saturday, the German Research Centre for Geosciences (GFZ) said.
According to GFZ, the quake was at a depth 10 kilometres.
The United States Geological Survey (USGS) pegged the magnitude at 7.4, with a depth of 39.5 km.
The Pacific Tsunami Warning System said there was a threat of a tsunami.
In Japan, to the southwest of the Kamchatka Peninsula, no tsunami warning has been issued, broadcaster NHK reported, citing the Japan Meteorological Agency.

Saudi Arabia says shrapnel from intercepted ballistic missile in Asir injures one
Nine injured in Australia as car crashes into crowd north of Sydney
India's 'cockroach' youth party to protest, demand poll chief's resignation
Congo's Ebola outbreak has killed more than 4,000, government data shows
About 400 French schools closed as some student protests turn violent
