Record rainfall devastated parts of Japan on Saturday, killing at least 30 people, as homes disappeared beneath floodwaters and landslides, and authorities ordered over 1.9 million evacuations.
The unprecedented downpours have wreaked havoc primarily in the west of the country, with flash floods and landslides leaving dozens more missing in addition to those killed.
A local official in Ehime, in western Japan, said the toll in his area had jumped from six to 16, bringing the official national fatality figure to at least 30 dead since the massive rains began Thursday.
But that figure was expected to rise further, with public broadcaster NHK saying the toll was at 49.
"The number of casualties is expected to increase as we are still in the middle of collecting information," Yoshinobu Katsuura, a disaster management official of Ehime prefecture, told AFP.
Prime Minister Shinzo Abe warned "the situation is extremely serious" and ordered his government to "make an all-out effort" to rescue those affected.
The floods have blanketed entire villages, submerging streets up to roof level. In some places, just the top of traffic lights could be seen above the rising waters.
"My house was simply washed away and completely destroyed," Toshihide Takigawa, a 35-year-old employee at a gas station in Hiroshima, told the Nikkei daily.
"I was in a car and massive floods of water gushed towards me from the front and back and then engulfed the road. I was just able to escape, but I was terrified," 62-year-old Yuzo Hori told the Mainichi Shimbun daily in Hiroshima.
Authorities have issued their highest level of alert for the rains and ordered more than 1.9 million people to evacuate their homes, mostly in western Japan.
But the orders are not mandatory, and many people have become trapped inside homes that were engulfed by floodwaters or hit by landslides.
- 'Rescue us quickly' -
The deadly rains began earlier in the week, claiming their first victim on Thursday when a construction worker was swept away by floodwaters in Hyogo prefecture in western Japan.
The toll has risen steadily since then, with many of those reported missing later confirmed dead.
The victims included a man in his sixties whose body was found near a bridge in Hiroshima on Saturday. Another man was killed in the same region when a mudslide struck his house, a local government official said.
The conditions hampered rescue operations, with some desperate citizens taking to Twitter to call for help.
"Water came to the middle of the second floor," a woman in Kurashiki, Okayama wrote, posting a picture of her room half swamped by flooding.
"The kids could not climb up to the rooftop," she said. "My body temperature has lowered. Rescue us quickly. help us."
In Okayama region, residents were sitting on top of their homes waiting for help as the rainwater swirled below. Helicopters were being flown over several affected areas to help airlift those affected to safety.
In Hiroshima, a wooden bridge was washed away entirely by a rain-swollen river and rescuers dug through the dirt as landslides crushed houses in the same region.
The government has deployed nearly 50,000 troops, police and firefighters for rescue operations, Chief Cabinet Secretary Yoshihide Suga said.
Defence Minister Itsunori Onodera said another 21,000 troops were on stand-by, adding: "I instructed them to carry out rescue operations by using every possible means of land-sea-and-air forces."
Several major manufacturers, including carmakers Daihatsu and Mitsubishi, said they had suspended operations at plants in the affected areas, Kyodo news agency reported.
Japan's Meteorological Agency has issued warnings at the highest level of its alert system -- only issued when the amount of rain is expected to be the highest in decades -- for large parts of western Japan.
By Saturday night, the agency had begun lifting its warnings in part of the country, though its officials told reporters heavy rain was forecast to continue until Sunday in western and eastern Japan.
Intense rainfall triggered huge landslides and flash floods in Hiroshima, Okayama, Kyoto and other regions
Some areas were hit by more than a metre of rainfall, according to the government