Little Pee Dee river .jpg (copy)

Floodwaters from the Little pee Dee River Tuesday, Sept. 18, 2018 flow close to the top of the bridge on Highway 76 North headed into Nichols,S.C.. Grace Beahm Alford/Staff

Tropical Storm Florence's death toll in South Carolina continued its rise on Tuesday after a jail transport van carrying two inmates was overtaken by flood waters.

The Horry County Sheriff's Office transportation vehicle was carrying the "detainees" from Conway to Darlington and traveling westbound on U.S. Route 76 about a half mile from the Little Pee Dee River when it was overtaken by the water, according to information provided by the Sheriff's Office. 

Tim Harper, administrator for Marion County, said the incident happened at 6:08 p.m.

"The two deputies attempted to extricate the persons being transported," the Sheriff's Office stated. "Despite persistent and ongoing efforts, floodwater rose rapidly and the deputies were unable to open the doors to reach the individuals inside the van."

High-water rescue teams arrived at the scene and retrieved the deputies from atop the van, the Sheriff's Office stated. 

Efforts to recover the inmates were ongoing Tuesday night, the Sheriff's Office stated. Their bodies could not be removed from the vehicle because of rising waters and other dangerous conditions.

State Law Enforcement Division agents are investigating the incident and the Marion County Coroner's Office will identify the deceased inmates. 

Horry County Sheriff Phillip Thompson called the incident a tragedy and said his agency is cooperating fully with SLED.

All lanes of Route 76 in the section the van was traveling on were closed due to flooding on Tuesday night, according to the S.C. Department of Transportation. 

Florence dumped significant amounts of rain on the Pee Dee. 

Nearby Marion received more than 19 inches, according to a preliminary report on the storm's rainfall by the National Weather Service. Galivants Ferry, located further down the river in Horry County, saw more than 16 inches. 

As of late Tuesday night, 37 deaths have been attributed to Florence, including eight in South Carolina. 

Reach Gregory Yee at 843-937-5908. Follow him on Twitter @GregoryYYee.

Gregory Yee covers breaking news and public safety. He's a native Angeleno and previously covered crime and courts for the Press-Telegram in Long Beach, CA. He studied journalism and Spanish literature at the University of California, Irvine.