Heavy downpours lashed South Korea a ninth day on Monday as rescue workers struggled to search for survivors in landslides, buckled homes and swamped vehicles in the most destructive storm to hit the country this year.

At least 40 people have died, 34 others are injured and more than 10,000 people have had to evacuate from their homes since July 9, when heavy rain started pounding the country. The severest damage has been concentrated in South Korea's central and southern regions.

In the central city of Cheongju, hundreds of rescue workers, including divers, continued to search for survivors in a muddy tunnel where about 15 vehicles, including a bus, got trapped in a flash flood that may have filled up the passageway within minutes Saturday evening.