One person was killed and eight others were injured in an apparent chemical explosion at the General Motors plant in Marion, Ind.
Of the eight people injured, three declined to be taken to the hospital. The other five victims were hospitalized with non-life-threatening injuries.
The man killed was identified as 48 year old James L. Gibson, who was a contract employee.
The building showed no apparent signs of damage and third shift workers were asked to report as they normally would.
There are close to 1,600 employees who work at the plant that provides blanks, stampings and sheet metal assembly for vehicles to GM assembly plants across North America.