FREMONT COUNTY, Idaho -

A one-car crash near Island Park Saturday morning proves deadly.

Police say just after 6 a.m. Joshua Brown, 18, of Macks Inn, was eastbound on U.S. Highway 20 near Pine Haven Road in a red Ford Escort when for unknown reasons he drove off the shoulder of the roadway and down the embankment.

The vehicle then hit the embankment of North Pine Haven Road and became airborne, coming to rest in a stand of trees. Brown was transported by air ambulance to Eastern Idaho Regional Medical Center in Idaho Falls with unknown injuries where he later died.

The crash is still under investigation.