Devon & Somerset Fire & Rescue Service were called to a report of a smell of burning coming from a derelict school building on Lyngford Road in Taunton at 18:38 this evening (Saturday).
Two fire appliances from Taunton, one fire appliance from Bridgwater and an operational assurance officer were mobilised.
On arrival crews confirmed smoke was issuing from the derelict school building and gained entry to the site to investigate further.
Fire crews confirmed a small fire in the kitchen area of the building and extinguished the fire using two breathing apparatus, one hose reel jet, one safety jet, one thermal image camera and a positive pressure fan.
There was 20% damage by fire and the remainder by smoke.
The fire service said police were requested to attend due to the fire being deliberate.