South Korea storm toll rises

South Korea struggled to recover Thursday from the nation’s heaviest rainfall in decades, a torrential two-day downpour that triggered landslides and flooding, killed at least 57 people and left countless others missing or stranded.

Military officials scrambled to retrieve explosives swept away by the storm. In one incident, a military ammunitions depot collapsed under a landslide, and officials said only half of the explosives, including 93 land mines, had been found.

They also worked to retrieve numerous Korean War-era land mines that were dislodged by the storm from grounds near an air-defense unit outside Seoul. The officials warned residents that 10 of those mines remained missing.

“Chances are low that the mines will be spotted,” Defense Ministry spokesman Kim Min-seok told reporters.

By the hour, a water-weary nation continued to take toll of its dead, who included 10 university students volunteering at an elementary school and the 63-year-old wife of a department store magnate who drowned while investigating the flooding in the basement of her upscale home.

Dozens of homes in hillside areas of metropolitan Seoul were damaged by cascading mudflows that officials said killed at least 17 people. In the city of Chuncheon, about 50 miles northeast of Seoul, landslides swept away several residential buildings. Thirteen people were reportedly killed, including the 10 students, and 26 were injured.

Elsewhere, seven people died after a river tributary just outside Seoul overflowed Thursday. In another nearby community, a factory roof collapsed in the rain, killing three workers and injuring two.

Late Thursday, thousands of firefighters, soldiers and other emergency workers used heavy machinery and shovels to comb water-clogged communities for the missing, with some teams carrying out bodies on stretchers.

Emergency sirens blared around the clock in Seoul, where the sudden deluge paralyzed the city, closing schools and businesses, flooding subway stations and knocking over pedestrians with torrents of water.

At one station, commuters used shovels and brooms to try to kee the platform from flooding. Street traffic also was clogged, with flooding closing roads and causing hours-long delays in some areas.

Seoul officials reported that scores of people had taken refuge in emergency shelters. More than 700 houses and 4,000 vehicles remain submerged.

President Lee Myung-bak visited a disaster command center, urging citizens to stay calm.

“Please make sure to take thorough measures and cope with the aftermath through close contact with local governments,” he advised residents.

More than 17 inches of rain had fallen on Seoul since Tuesday, about 15 times the average two-day rainfall this year, weather officials said, and 10 more inches could fall Friday.

South Korean news reports said the dead university students, members of an organization called Idea Bank, had been staying at a motel since Monday and were having a meeting when the structure was hit by a landslide. Most of the victims were staying on the first floor.

“Because of this sudden accident, the people on the second floor were rescued by ladder, but students on the first floor were hit hard,” one survivor told reporters.

john.glionna@latimes.com

Jung-yoon Choi of The Times’ Seoul bureau contributed to this report.