ST. LOUIS (AP) -- At least 10 people were injured, three critically, in an explosion Thursday at a steel castings plant in southwestern Illinois, officials said.
The blast happened shortly after 8 a.m. in the cleaning-and-finishing department at the American Steel Foundries plant in Granite City, just northeast of St. Louis. Roughly 800 people work at the plant where the company produces railcar undercarriages and related components, said Mike Right, the United Steelworkers union's health, safety and environment chief.
Seven workers were treated for smoke inhalation at the Gateway Regional Medical Center, while three others in critical condition were flown by helicopter to other hospitals for treatment, Gateway spokeswoman Kate Allaria said.
Two of them were treated at Mercy Hospital in Creve Coeur, where spokeswoman Bethany Pope said she could not discuss their medical conditions. It was not clear where the other worker was being treated.
Federal workplace safety officials are investigating the cause of the blast. Calls and emails to the business went unanswered Thursday.
Robert Lott, a worker at the plant and president of the United Steelworkers Local 1063, told the Belleville News-Democrat that at least two of those injured may have suffered broken legs and internal injuries. He said he believed the blast was caused by a gas leak.
"I could see flames, initially, and then the visibility went down to zero from the dust that fell from the rafters," said Lott, who was about 100 yards from where the blast happened.
Mike Right said the union was sending an investigator to the Granite City plant "to make sure we learn the lessons and really understand what happened."
"At this point everything is pretty sketchy, and we really don't like to comment on causes until we have them tied down," he said.