New tremors have hit east of the Kuril Islands in the Pacific Ocean, which are disputed between Russia and Japan, hours after a 7.4 magnitude earthquake, the United States Geological Survey said on Friday.
The 4.9 magnitude tremor hit roughly in the same location as the earlier quake, 315 kilometres (195 miles) east of the Russian town of Severokurilsk and 1,830 kilometres (1,130 miles) northeast of Tokyo, the USGS website said.
Russia's Geophysics Service did not report any tsunami threats or damage from the new tremor, the RIA Novosti news agency reported.
The sparsely populated, earthquake prone Kuril Islands are the subject of a long running territorial dispute between Russia and Japan.
Tokyo claims four of the islands off Japan's northern island of Hokkaido, which were seized by Soviet troops in 1945 and have been held by Moscow ever since.
The dispute has kept Russia and Japan from signing a peace treaty to formally end World War II.