TOMAHAWK, Wis. - One man is dead and another critically hurt after being burned by fly ash at a mill in Tomahawk.

The accident happened just before 8:30 a.m. Tuesday at Packaging Corp of America, or PCA. The company produces containerboard and corrugated packaging.

A human resources manager with PCA tells WSAW-TV the company does not know exactly what happened. The injured men were contractors, not employees of PCA, and are from Ontonagon, Mich. They were working for a company based out of Ontonagon.

The Lincoln County sheriff's office says a 47-year-old man died from his injuries. A 29-year-old man was flown to the UW-Madison burn center. The extent of his injuries is not known.

Fly ash is produced during combustion of coal.

The Lincoln County coroner's office has joined the investigation.

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