Deputies said 40-year-old Tammy Callins of Martin, TN was northbound on the parkway near the 26 mile marker when she lost control of her car. According to deputies, Callins' car struck a bridge and came to rest in the northbound traveling lane of the parkway.
Deputies said Callins was not wearing a seatbelt and was unconscious when emergency workers arrived due to a head injury. Police also said a small fire broke out in the engine of the car and was extinguished by a motorist that was passing by.
Deputies said Callins was transported by ambulance to Jackson Purchase Medical Center, where she was flown by helicopter to Vanderbilt University Medical Center in Nashville, TN.