A Plant City woman who was asleep in the back seat of a car without a seatbelt was killed early Monday in a crash on County Road 39 in rural Lithia, deputies said.

Sonia E. Roldan, 22, was riding in the back seat of a 2001 Toyota when Hector Estrella Jr. drove off the road south of Old Welcome Road at about 55 mph. and struck a culvert, the Hillsborough County Sheriff's Office said.

Roldan was ejected as the car overturned, and she died at the scene.

Investigators said alcohol appears to be a factor in the crash and that charges are pending toxicology tests.