Torrential rainfall and flooding has battered a widespread area in Japan, with local media reports putting the death toll at 38.
Public broadcaster NHK said another four people were seriously injured and 47 are missing.
TV footage showed a residential area in Okayama prefecture with brown water spreading like a huge lake. Some people fled to rooftops and balconies and waved furiously at hovering rescue helicopters.
Throughout the affected areas, parked cars sat in pools of water. NHK TV said water had reached as high as 16ft in the worst-hit areas.
Kyodo news service, which put the death tally at 34, said one death was in a landslide in Hiroshima, which had set off a fire, while the body of a child was found in another area.
NHK said a woman died in her home in Hiroshima when it got buried in a mudslide.
In Ehime prefecture, a woman was found dead on the second floor of a home hit by a landslide, Kyodo said. Also in Ehime, two primary school girls and their mother who got sucked into a mudslide were rescued but their hearts were not beating, it said.
Kyoto prefecture said it was working to control flooding at several dams and identified one fatality as a 52-year-old woman.
Military water trucks were rushing to areas where water systems were no longer working, Okayama officials said. Troops in camouflage outfits helped people and pets reach dry land on small military boats.
Evacuation orders or advisories were sent for 4.72 million people, and 48,000 members of the Self-Defence Forces, police and firefighters were mobilised for search missions, according to Kyodo.