A series of powerful earthquakes have shaken the northern Japanese island of Hokkaido.
Japan's Meteorological Agency measured the initial quake at 8.0 on the Richter scale - strong enough to cause major damage - and warned there could be aftershocks for up to 10 days.
The earthquakes injured more than 230 people, caused widespread damage and blackouts, and prompted officials to issue tidal wave warnings.
Quake-generated waves measuring about one metre in height struck the eastern Hokkaido coast, washing away some empty cars, but no major wave damage was reported.
The focus of the first quake, which was felt in Tokyo about 975 kilometres to the south, was 42 kilometres below the seabed in the Pacific Ocean near the port of Erimo.
A second quake measuring 5.8 on the Richter scale jolted Hokkaido about an hour later followed by another measuring 7.0.
The meteorological agency issued a tsunami warning for the coastal areas in eastern and central Hokkaido and a tsunami alert for the coastal areas in western Hokkaido as well as the northern Japanese prefectures of Aomori, Iwate, Miyagi and Fukushima.
Hokkaido, about the size of Austria, is the second-largest of Japan's four main islands and has a population of more than five million. The capital, Sapporo, hosted the 1972 Winter Olympics.