Television footage showed residents wading through muddy, knee-deep water on streets. Others shoveled out mud from their homes.

Local officials said damage was concentrated in Kumamoto and neighboring Oita states on Japan's southern island of Kyushu. Most victims were in their 70s and 80s.

Hundreds of homes were destroyed or damaged, and tens of thousands of people had to evacuate the area threatened by swollen rivers and mudslides.

The Meteorological Agency said as much as 50 centimeters (20 inches) of rain fell overnight. It predicted up to 20 centimeters (8 inches) of rainfall through Friday.

Rescue workers and defense troops have been sent to the region to help. Some residents trapped in inundated areas were airlifted by helicopters.

The heavy rains also disrupted local train services, blocked off roads and left about 22,000 homes without electricity. (AP)