A Greenville, S.C., truck driver is facing a second-degree vehicular manslaughter charge in a horrific, fatal accident earlier this month on I-85 in Gwinnett County.

Thomas Caldwell, 67, also was charged with making an unsafe lane change in the July 8 accident, Gwinnett police said Friday.

Caldwell’s tractor-trailer was traveling south on I-85 near Steve Reynolds Boulevard when he changed lanes, forcing a Nissan Pathfinder, carrying four family members, out of its lane and into another truck, police said.

The Pathfinder left the road, struck a steep hill between I-85 and the Steve Reynolds ramp and flipped over several times before coming to rest on the ramp, investigators said.

A front-seat passenger, Rabia Adnan, 32, of Duluth, was thrown from the Nissan and later died. Her two children, ages 7 and 4, were taken to the hospital but later released to their father, who was the driver.

Caldwell did not stop, but police did not charge him with hit-and-run, police said.

A police spokesman said Friday that, while investigators concluded that Caldwell caused the accident by making an unsafe lane change, they found no evidence that his tractor-trailer struck the Nissan Pathfinder.

Caldwell turned himself in Thursday and has been released on bond.