MEMPHIS (AP) – Officials say one refinery worker has died after being exposed to a hazardous substance at a Valero refinery in Memphis.

Martha Deacon, a spokeswoman for the Tennessee Department of Labor and Workforce Development, says one of two workers who were injured in Monday morning's hazmat incident at the southeast Memphis plant has died.

Memphis Fire Department spokesman Wayne Cooke says the workers were exposed to a mixture of propane and hydrofluoric acid when a sight glass on a pump unit ruptured.

Cooke said two firefighters also were exposed to the substance.

One worker was transported to a hospital in critical condition, but it was not immediately if that's the worker who later died. The other worker and the firefighters were taken to a hospital in non-critical condition.

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