Investigators now believe they know what caused a massive explosion that rocked the Kosan Crisplant Propane Facility in Marshfield on the 13th of May.
Eye-witness accounts indicate that a propane cylinder that was dropped, accidentally sparked the fire.
The say it happened near a loading dock where the cylinders were being reconditioned.
The fire took more than 3 hours to get under control and over a day to stop.
More than 10,000 propane tanks in total exploded in the fire.