Deputies with the Horry County Sheriff's Office were transporting the two women, who have not been identified, to another facility on Highway 76 when they hit rapidly rising floodwaters, Sheriff Phillip Thompson said in a statement.
"I'm not sure if it was the way the van was positioned, against a guardrail, or if it was pressure from the water, but unfortunately they were not able to get the van doors open and get the ladies out", Thompson said. Greenville Online reports that neither woman had a criminal record.
Two mental health patients in SC have died after being inside a transport van that flooded.
The family says Green had three children, but had lost one child to cancer in 2015. "I just want to say to the families that they are definitely in our thoughts and our prayers". That effort resumed Wednesday morning, but Thompson said a specialized crew was being flown in from Charleston to assist.
By the time a rescue team arrived, the deputies were stranded on top of the van and it was too late for the women. Officials said that the transport van was near the Little Pee Dee River, one of the bodies of water that state officials are watching following the heavy rains of Florence.
Marion County coroner Jerry Richardson told HuffPost on Wednesday that the submerged van had to be left overnight with the women's bodies still inside because of the danger it posed to rescue workers. The women remained chained in the van.
Investigators are in the early stages of conducting interviews and gathering evidence, SLED spokesman Thom Berry said.
Some roads in Marion and Horry County are impacted by floods after Hurricane Florence passed through the area. "People need to know exactly how it happened. We are just very sorry that this event has taken place".
The South Carolina Law Enforcement Division is reportedly investigating the circumstances surrounding their deaths.
The incident is under investigation and the deputies are on administrative leave. They were women who voluntarily sought help. There was no answer at a number listed for Bishop.
Richardson said the deputies and two patients began the trip that afternoon from a hospital near Conway, where tributaries of the Pee Dee River are overflowing their banks.
The patients were being taken from Loris Hospital and Waccamaw Mental Health Hospital to McLeod, according to WPDE.
The sheriff said his agency acts as a courier in such situations, to follow a judge's wishes. Their names also yielded no records in the Horry County jail and court index systems.
Facebook/Jewels Green Nicolette Green pictured on her sister's Facebook page.