The fire happened at a factory between Phoenix Parkway and Bangrave Road in Corby.
At its height there were ten pumps in attendance and it's believed fire fighters will be on the scene for the rest of the day and into tomorrow.
No-one is thought to have been injured in the blaze.
It's unclear at this time what caused the fire.
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Cloud clearing, then a dry, bright and warm day.
Ending warm with some sunshine.