An earthquake measuring 6.8 struck northeast Japan triggering a tsunami warning on Wednesday, according to the U.S. geological survey.
Seismologists said the epicenter of the quake was 260 kilometers southeast of the Port of Kusiro on the island of Hokkaido. The earthquake's epicenter was 10 kilometers below the surface.
A magnitude 6.8 aftershock ocurred after the initial earthquake, the geological survey said.
A tsunami alert was issued for Japan's Aomori and Iwate prefectures with waves expected to be below 50 centimeters (1.5 feet).
The tremor was felt in Russia's Kuril Islands, but no damage or casualties were reported there. No tsunami alert was issued for the region.
A 6.1-magnitude aftershock with an epicenter at the depth of 10 km rattled the area later in the day. Tremors were felt in the Ibaraki, Chiba, Fukushima, Tochigi, Saitama and Miyagi prefectures and in the capital Tokyo.
