A powerful 7.5-magnitude earthquake struck off the Kurile Islands on March 24, causing a small tsunami and prompting a tsunami alert on the western coast of the United States and Canada and as far away as Hawaii.
The U.S. Geological Survey said the quake struck at 10:49 p.m. 219 kilometers south-southeast of Severo on the Kurile chain northeast of Japan.
The epicenter was 56 kilometers deep, the Geological Survey said.
Russia's Emergencies Ministry reported a small tsunami with a wave of about 50 centimeters high.
The Pacific Tsunami Warning Center said "only very small tsunami waves were generated by this earthquake and there is no further threat."
The four southernmost islands of the Kurile chain have been disputed between Moscow and Tokyo since the end of World War II.
The Kuriles are known as the Northern Territories in Japan.
Lingering tensions over the islands have prevented Japan and Russia from signing a peace treaty to formally end the war.