West Sussex Fire and Rescue Service said they responded to a fire at a premises in Cuckfield Road at 8.45pm.
"Upon arrival crews found a fire in the kitchen and used four sets of breathing apparatus, two hose reels and two jets to extinguish the blaze, which was of accidental ignition.
“This morning firefighters carried out a further inspection and have confirmed the incident is now closed.”
A spokesperson for South East Coast Ambulance Service (SECAmb) said: “Ambulance crews joined fire crews at the scene and one person was assessed and treated before being taken to hospital for further treatment.”
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