Witness Jean-Luc Howe said to Somerset Live that the fire was in the staff accommodation at the resort in Somerset around 3pm.
Two fire engines are the scene and Jean-Luc claimed a “whole block of accommodation was up in flames”.
Flames and smoke can be seen rising from the resort in pics from the scene.
Butlin’s claimed the fire was small.
It said on Twitter: “We are pleased to share that this was isolated to just one caravan.
“Everyone is ok and none of guest caravans were affected.”
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