BIRON, Wis. (AP) -- An explosion at a paper mill in central Wisconsin has injured three workers, including one who was airlifted to a hospital with severe burns.

NewPage Corp. spokesman Cliff Bowers says the accident occured Friday about 8:15 a.m. at the company's Biron (BIHR'-in) plant.

He tells The Associated Press it happened near the mill entrance where coal is delivered. He says a fire was sparked in the coal dust-collection system.

Bowers says one worker was burned and airlifted to a hospital, while two others were taken to a hospital by ambulance. He says the company isn't immediately releasing their names.

Bowers says firefighters fought the blaze for more than an hour.

NewPage is based in Miamisburg, Ohio. Bowers says the Biron plant has 429 employees.