A biodiesel plant in Mississippi is on fire after two explosions Wednesday morning.

Union County Emergency Management Director Curt Clayton told WTVA that two workers were inside the North Mississippi Biodiesel plant in New Albany at the time of one explosion, but both escaped injury. Nearby residents told the station that they had heard two blasts.

The Mississippi Highway Patrol said the fire is so intense that firefighters have not been able to get close, Fox 13 reports.

The blaze has shut down Highway 15 and authorities are trying to determine the cause of the explosion.

The Mississippi Department of Environmental Quality is testing air in the area for the presence of any hazardous materials, but has not found anything yet, WTVA reports.

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