Authorities in South Carolina said two detainees were killed Tuesday night when a jail transport van was swept away by floodwaters. The Horry County Sheriff’s Office transportation vehicle was traveling on U.S. Route 76 near the Little Pee Dee River when it was overtaken. Two Horry County Sheriff’s Office deputies in the vehicle managed to free themselves but were “unable to open the doors to reach the individuals inside the van,” according to a statement from the Horry County Sheriff’s Office. Marion County Coroner Jerry Richardson told the Associated Press that the two victims were female, though they have not yet been identified. Local reports said the two women were mental-health patients being driven to a behavioral-health center. State Law Enforcement Division agents are investigating the incident.