South Korean rescue workers pulled seven bodies from a flooded tunnel where around 15 vehicles were trapped in muddy water, as days of heavy rain triggered flash floods and landslides and destroyed homes across the country. Flooding and landslides have killed at least 33 people in Korea and forced thousands to evacuate, officials said Sunday.

Nearly 400 rescue workers, including divers, were searching the tunnel in the central city of Cheongju, where the vehicles, including a bus, were swamped by a flash flood Saturday evening, Seo Jeong-il, chief of the city’s fire department, said in a briefing. Fire officials estimated that the tunnel filled with water in as little as two or three minutes.