WAGNER, Wis. — A 38-year-old man involved in a motorcycle crash in Wagner, Wis., on Saturday has died, according to a release from the Marinette County Sheriff’s Office.

The Marinette County medical examiner was notified Tuesday the man — identified as Jay Shipla of Green Bay, Wis. — died of head injuries at a Green Bay hospital, the release stated.

Deputies were called to the crash at 3:45 p.m. on Saturday and determined Shipla was driving west on County X near Philipps Road when he failed to negotiate a curve and left the roadway, striking a tree.

Shipla was alone and not wearing a helmet, the release stated.

The crash remains under investigation by the sheriff’s office and the medical examiner.

This is the fourth traffic fatality in Marinette County this year.

Deputies were assisted by the Wagner Fire Department and the Bay Area Medical Center Paramedic Service.