HARRISBURG, Pa. (AP) – A riding lawnmower being used by a longtime groundskeeper at a Pennsylvania university has caught fire, killing the groundskeeper.

Millersville University President John Anderson says in an email to faculty and students the worker died Wednesday. He says 60-year-old Michael Keefer was riding on the lawnmower near the university’s stadium when the fire broke out.

READ MORE: Pittsburgh Police Safely Locate Missing 14-Year-Old Joseph Freund

Keefer was taken to a hospital and died that night.

The Lehigh County coroner’s office on Thursday said cause of Keefer’s death was thermal injuries and the death was an accident.

Join The Conversation On The KDKA Facebook Page
Stay Up To Date, Follow KDKA On Twitter

READ MORE: Redistricting Committees Named In West Virginia

A university spokeswoman tells LNP it’s unclear what caused the fire.

The university and the state fire marshal are investigating.

Keefer had worked at the university since 1990.

MORE NEWS: Man Stopped In March For Stolen Scratch-Off Tickets Now Facing Additional Drug And Firearm Charges

(Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)