One person died and two others were missing after heavy rains that have pounded South Korea's central and northwestern regions over the past three days, the National Emergency Management Agency said Saturday.

The deceased was found in Ansung City, some 80 kilometres (50 miles) south of Seoul, while two others disappeared in Jincheon County, 110 kilometres (69 miles) southeast of capital, the agency said.

The two cities were deluged by up to 258 millimetres (10.3 inches) of rain between early Friday and early Saturday.

Almost 700 people were forced to seek shelter in public buildings as torrential rain destroyed or flooded houses, mainly in central Chungcheong and northwestern Gyeonggi.

Bridges were swept away, roads destroyed and rice paddies deluged in the two provinces, where heavy rain alerts have been in effect since Friday. Up to 80 millimetres (3.2 inches) more is expected by Sunday.

Seasonal monsoon rains have lashed South Korea for the past two weeks, fed by two recent typhoons.

The rains over the period have left 31 people dead and 17 others missing, the agency said, causing more than 1.3 billion dollars worth of damage mostly to homes, roads, briges and farmland.