Residents living on the outskirts of Cupar were put on high alert last Friday evening as the massive blaze at the ABN Mill to the south-west of the town continued, although firefighters were able to bring the incident to a safe conclusion without the need to evacuate nearby homes.
With the fire brought under control, crews remained at the scene throughout Saturday to damp down the affected parts of the building and ensure the area was safe as investigators began the arduous task of examining how the blaze started and how it spread so quickly.
The fire and rescue service said crews finished up at the site on Saturday afternoon and confirmed the cause was still "under investigation," adding it could take several days before any outcome is known.
It is understood one sector of the building alone contained an acetylene cylinder, 10,000 litres of fuel oil and 3000 litres of acid.
A 30,000 litre tanker of fuel oil outside the building also had to be cooled by firefighters as the building showed signs of collapse and huge explosions could be heard inside.
Residents in the immediate vicinity were advised to remain indoors with windows closed due to the large smoke plume involved.
Nobody was injured in the fire and all of the staff working at the mill have been accounted for.