Authorities are investigating the death of man who appears to have suffered a medical emergency while behind the wheel of a car driving on the Bass Highway in the state's north.
Police say the vehicle went through safety rails on the side of the road and came to rest adjacant to train tracks at Hagley on Friday afternoon.
An off-duty firefighter provided assistance until paramedics arrived, but the 68-year-old was pronounced dead at the scene.
The road was closed for around 2 hours while investigators examined the scene.
"No other vehicles were involved in the incident but a TASRAIL train had to be held at Westbury while the rail tracks were cleared and checked," a police statement said.
An exact cause of death is yet to be determined.
It was the second fatality on the Bass Highway in the space of 24 hours, following the death of a Victorian 56-year-old female motorcyclist at Wynyard.