Authorities in the area have issued warnings to the public to avoid the area so that rescue vehicles can get through.
Chris Davis, sheriff in Humphreys County, tells NBC News:
At this time, we have been able to confirm that we have 19 people we are looking for. I can say that we have had fatalities. I do not want to give any number.
The management of the factory confirms that the explosion has claimed several lives, but does not want to release details as long as the rescue work is in progress.
It is said to have been impossible for rescue workers to initially enter the facility as several explosions followed each other.
The facility manufactures explosives for both military and civilian purposes.
Aerial photographs show a completely destroyed building with smoldering wreckage and vehicle wrecks all around.
It is still unclear what caused the explosion. According to Sheriff Chris Davis, it may take several days to investigate exactly what happened.
