JEFFERSON COUNTY, Mo. (News First) – Two teenagers were injured in a one-car crash Sunday night in Jefferson County. The Missouri State Highway Patrol says the accident happened northbound on Highway 21 south of Lembeck Lake Road, just outside of De Soto when a 2004 Chevrolet Monte Carlo driven by 18-year-old Casey L. Horn of Bonne Terre ran off the left side of the road and hit multiple trees. Horn was moderately injured as was his passenger, 19-year-old Jordan N. Burnett of De Soto. Both were taken to Mercy Hospital South in South County for treatment of their injuries.