Heavy rains Saturday triggered landslides, flooded buildings and left 560 people homeless, government officials said. A 42-year-old woman was missing in a rain-swollen river.
The downpours measured up to 13.4 inches and hit towns around Seoul, officials said.
Weather officials forecast two to 4 more inches of rain for the next 24 hours and asked people in low-lying zones to evacuate or listen to radio broadcasts.
One area hit especially hard was Dongduchon, where 1,500 people were evacuated to nearby schools and highlands, the officials said.