At least 100 people are thought to have died after record rainfall caused flooding and landslides in western Japan, a government spokesman says.
More than 50 others are believed to be missing, the Japan Times reported.
Since Thursday, parts of western Japan have received three times the usual rainfall for the whole of July. Two million people have been ordered to evacuate as rivers burst their banks.
"We've never experienced this kind of rain before," a weather official said.
Rescuers restarted their search through the mud for any survivors or the bodies of those killed on Monday morning.
An official in Okayama prefecture told AFP news agency that water levels were gradually receding and that emergency teams may be able to access the worst-hit areas on foot.
Most of the deaths have occurred in Hiroshima prefecture.
Officials say water levels in some areas have receded
Tens of thousands of rescuers, including police and soldiers, are taking part in search operations
Prime Minister Shinzo Abe said on Sunday that rescuers were "working against time".
"There are still many people missing and others in need of help," he told reporters.
Residents in Okayama prefecture rescue dogs from a flooded area
In the town of Motoyama, on Shikoku island, 583mm (23in) of rain fell between Friday morning and Saturday morning.
Further rain warnings are in effect, with more than 250mm predicted to fall in some areas by Monday.