Cars, ships and buildings were swept away by the tsunami after the 8.9-magnitude earthquake which struck about 400km north-east of Tokyo.
Officials say 350 people are dead and about 500 missing, but final death toll might be much higher. Concerns are raised over possible radiation leaks from 2 nuclear plants near the earthquake zone.
The tsunami went crashing through villages as it was a 30ft wave. The town of Rikuzentakata, in northern Iwate, was largely submerged in muddy water, with no sight of houses or buildings of any kind.