Weather officials in Japan have issued an emergency warning for heavy rain in Saga, Fukuoka and Nagasaki prefectures in northern Kyushu.
The downpours were triggered by a weather front.
Parts of Saga Prefecture got more than 100 millimeters of hourly rainfall.
One man was found without vital signs in a car that was washed away.
There are also reports of mudslides in the prefecture. Some areas are reportedly inundated after water spilled over riverbanks.
The emergency warning is the highest alert level on the disaster warning scale of one to five.
The Meteorological Agency is advising residents to immediately head to an evacuation center.
If it's dangerous to do so, it's instructing people to move to a safer location inside the building they're in now.