At least eight people were killed and seven others reported missing after some of the heaviest rainfall in decades drenched the greater Seoul region. The floods turning the affluent streets of the South Korean capital’s Gangnam district into a river of submerged vehicles and overwhelmed public transport systems.

Torrential rain began on Monday morning and intensified through the evening hours. The downpours flooded streets and subway stations and damaged nearly 800 buildings in Seoul and nearby cities, while more than 790 people were forced to evacuate from their homes, the Ministry of the Interior and Safety said.

Commuters were slowly returning to work on Tuesday morning after emergency crews worked overnight to clean up much of the damage. But concerns remain as torrential rain was forecast for the second day in a row.

While most of the Seoul metropolitan area’s subway services were back to normal operations, about 80 roads and dozens of riverside parking lots remained closed due to safety concerns.

South Korean President Yoon Suk-yeol has called for public employers and private companies to adjust their commuting hours and called for officials to be aggressive in restoring damaged facilities and evacuating people in flood-affected areas to prevent further deaths.

The country’s weather agency maintained a heavy rain warning for the Seoul metropolitan area and nearby regions on Tuesday.