The crash occurred on U.S. Highway 84, one mile north of Coleman, Texas.
The vehicle is a Guardian EMS Ambulance stationed in Brownwood, Texas.
The Ambulance was returning to Brownwood after delivering a patient to an Abilene hospital.
Texas Highway Patrol Trooper Martin Molotsky responded to the crash. He reports that fatigue may have played a role.
No injuries were reported by either the driver or the other crew member.
The weather was clear and the roadway dry.