(CNN) -- An explosion at a Mississippi paper plant killed one worker Saturday and injured 17 others, according to authorities.
The blast at the International Paper plant in Redwood was caused by a boiler explosion about 3:15 p.m., said Nicole Vera, deputy director of 911 services.
Warren County Coroner Doug Huskey confirmed the death of a man, whose identity was withheld pending family notification.
About 400 workers were at the plant Saturday; 17 were taken to a nearby hospital, said John Adams, the plant's manager of environmental health and safety. All of the injured were contracted workers, though their employers weren't immediately known, he said.
Warren County Sheriff Martin Pace said five workers were taken to the burn unit of a hospital in Augusta, Georgia. Several other workers were critically wounded, he said.
No International Paper employees were hurt in the explosion, which remains under investigation, said company spokeswoman Amy Sawyer.
The explosion occurred during the start-up of a recovery boiler as the mill was undergoing annual maintenance, Sawyer said.
She said that before Saturday, the plant, which shut down operations after the blast, hadn't had any injuries for more than a year.
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