WHITESBURG, Ky. — A single-vehicle crash in Letcher County killed one person early Sunday morning.

According to Kentucky State Police, Jonathan Stewart, 30, of Thornton, was operating an off-road dirt bike on Route 1148, when he lost control due to slippery conditions, resulting in the bike striking the guard rail.

Stewart was pronounced dead at the scene by the Letcher County Coroner’s Office.

Police say Stewart was not wearing a helmet at the time of the crash. Toxicology results are pending. This incident remains under investigation by Trooper Kevin Day.