Four South Koreans were missing and one was hospitalized Sunday after they jumped into a rain-swollen river in an apparent group suicide attempt first conceived online, police said.
The group _ three men and two women _ jumped off a bridge amid heavy downpours in Gapyeong, about 40 miles (60 kilometers) northeast of Seoul, chief investigator Lee Young-su said. Police earlier said the group comprised two men and three women but later changed the information.
A 24-year-old woman was rescued by a boat operator after floating on debris for about an hour in the Bukhan river, Lee said. She was speaking to officials but had so far refused to say why she tried to kill herself, Lee said.
"These people met online. They tried to gas themselves to death the night before by burning charcoal briquets in a room," Lee said. "But it failed somehow."
Lee said the five drugged themselves with sleeping pills before jumping off the bridge. It was not immediately clear why they tried to kill themselves, Lee said.
Another police officer said heavy rain made it difficult for divers to search the river for the missing. He declined to be identified because he was not authorized to give details to the media.
South Korea has one of the world's highest suicide rates. Reports of group suicide surface occasionally. Economic difficulties, failed relationships and mental illnesses such as depression are often blamed.
South Korea is also one of the most densely wired countries in the world. Many people meet online to form personal and professional relationships.