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.

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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.

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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.

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