Old Saybrook — Police said a Niantic woman was killed Wednesday afternoon when she lost control of the car she was driving.

Mary C. Heath, 58, of 153 Pennsylvania Ave., Niantic, was driving south on Route 9 near the Interstate 95 northbound ramp in Old Saybrook when she lost control of her Toyota Corolla, drove off the roadway and struck a bridge structure, police said.

State police from the Troop F barracks in Westbrook responded shortly before 3:30 p.m. Wednesday. Heath was pronounced dead at the scene.

The accident remains under investigation.