A Greene County truck driver died Thursday night after the tractor-trailer he was driving left Tennessee Highway 81 in Washington County and struck a ditch.

A Tennessee Highway Patrol dispatcher, who was quoting from Trooper Suzanne Masoner's initial report, said authorities are still trying to determine if Carl Seaton, 76, of Greeneville, died from injuries suffered in the crash, or from a medical condition.

The accident was reported at 7:49 p.m. Thursday and took place along Highway 81 near Deacon Creek in the Embreeville community of southern Washington County.

The dispatcher said Seaton had been driving a 2005 Freightliner tractor that was pulling an empty trailer north on Highway 81 when the truck veered off the road and came to rest in a ditch about two miles from the Unicoi County line.

The crash shut down Highway 81 for several hours on Thursday night, according to the THP.

At about 9 p.m., Unicoi County authorities were re-routing northbound traffic from Highway 81 in Erwin onto Interstate 26.

An investigation of the accident is continuing, according to the THP.