Four more bodies have been recovered from a once-flooded underground road in central South Korea, bringing the number of people dead or missing in recent downpours to 49, officials said on Monday.

The Osong underground roadway in the central city of Cheongju was flooded on Saturday when a nearby river overflowed after an embankment was brought down by rising water levels due to heavy rain, leaving 15 vehicles, including a bus, trapped underwater. So far, 13 bodies have been recovered from the tunnel, Yonhap news agency reported.

Nationwide, 39 people, including 19 in the southeastern province of North Gyeongsang, had been reported to have been killed in the aftermath of the heavy rains that have pounded the country since last week as of 6 a.m., according to the Central Disaster and Safety Countermeasure Headquarters.

As of 6 a.m., nine people remain missing, including eight in North Gyeongsang Province, while 34 people have been reportedly injured.

Casualties could rise as rescuers continue an operation to drain and search the flooded underpass, where more than 10 vehicles are believed to be submerged.

Across the country, 10,570 people evacuated their homes due to rain damage, according to the office.

Downpours have also damaged 628 public facilities and 317 other private properties, including 146 roads that collapsed or were swept away and 139 flooded homes.

A total of 28,607 households across the nation had been left without electricity as a result of the heavy rains, and power was back in service at most of those households as of Monday.

According to the Central Disaster and Safety Countermeasure Headquarters, more than 500 millimetres of rain have pounded central and lower regions since July 9, including 626 mm in Gongju, South Chungcheong Province, 614 mm in the nearby county of Cheongyang, 580 mm in the central city of Sejong and 522 mm in Mungyeong, North Gyeongsang Province.

Heavy rain warnings were in place for the Chungcheong provinces, southern regions and Jeju Island as of Monday morning, and the weather agency said the Jeolla provinces and nearby areas may experience further rain of up to 40 mm per hour.

Through Tuesday, up to 200 mm of rain has been forecast for Chungcheong and southern regions, and between 10 mm to 100 mm for the rest of the country.