Five people were killed, including two unborn babies, when a 2003 Chevrolet Trailblazer headed for a hospital crashed Friday night in South Carolina, WLTX reported.

Troopers said 11 people had piled into the Trailblazer in Darlington County. One of the passengers was in labor, Darlington County Coroner Todd Hardee told WLTX.

Hardee identified the driver as Leonard Rouse, 52, and said the Trailblazer struck a drainage culvert and overturned on the highway.

Rouse was one of the five people killed. The others were Nakisha Rouse, 14; Chikari Douglas-Rouse, 28, and her unborn baby; and another unborn baby identified by Hardee as Douglas-Graham.

The remaining passengers were treated for serious injuries, WLTX reported. One person was in critical condition after surgery, the Darlington County Coroner's Office said. Two children were transported to the Medical University of South Carolina for treatment, WMBF reported.

The crash is the deadliest single-vehicle collision in more than 20 years in Darlington County, WMBF reported.

The mother of the unborn baby identified as Douglas-Graham was not one of the deceased victims, WLTX reported.