Feb. 27—LIBERTY TOWNSHIP — A teenager was killed and four people were injured in a crash Sunday afternoon in Liberty Township.

Mercer County Coroner John A. Libonati pronounced Derrick Hofmann, 17, Prospect, Pa., dead at the scene. He was a rear-seat passenger, according to Mercer County District Attorney Peter C. Acker, who was on the scene.

The driver and another occupant were flown by medical helicopter to Mercy Health-St. Elizabeth Hospital in Ohio with life-threatening injuries. The other two occupants were taken by ambulance to Grove City Medical Center with non-life-threatening injuries, Acker said.

The crash happened at 2:45 p.m. in the 2100 block of Mercer-Butler Pike Road (Route 258), just before Amsterdam Road, Libonati said.

Acker said the vehicle was traveling at excessive speeds when the driver lost control and the vehicle rolled.

Some of the occupants in the vehicle were not wearing seat belts, according to Acker.

"People need to wear their seat belts; they clearly save lives," Acker said. "And they need to obey the speed limits."

Sunday's incident was the third fatality of a rear-seat passenger in roughly six months, Acker said. In all three fatalities, the rear-seat passengers were not wearing a seat belt.

"In my 44-plus years of legal practice, a large portion of which involved motor vehicle accidents, I rarely saw rear seat passengers killed in a motor vehicle accident," Acker said. "Until recently, I probably could have counted them on one hand."

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