YANKTON - Authorities are investigating the death of a 23-year-old man whose body was found on a highway east of the city of Yankton.

The Yankton County Sheriff's Office says a preliminary investigation indicates that Joseph Bret Jackson of Yankton was killed in possible hit and run early Friday morning.

The body was found shortly before 4 a.m. Friday.

Sheriff Jim Vlahakis tells the Yankton Press and Dakotan that no witnesses of the incident have come forth.

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