A couple with their pet dogs on the roof of their house in the flooded city of Joso Photo: AP
A further 800,000 people across eastern Japan have been advised to evacuate after officials issued predawn warnings of unusually harsh rainfall to 5 million people.
Japanese military helicopters plucked dozens of residents from the tops of their home, but rescue officials said they were unable to keep up with the pleas for help after raging floodwaters swamped parts of a city north of Tokyo.