Five fire engines are on the scene in Aston Clinton as a car workshop is on fire.
Bucks Fire and Rescue confirmed that a full evacuation has taken place.
People living near the fire, which is in Harebridge Lane, Aston Clinton, which is close to Halton, are being advised to keep doors and windows shut.
Bucks fire and rescue posted: "Crews are currently at the scene of a fire at a car workshop in Harebridge Lane, off Upper Icknield Way, Aston Clinton.
"Residents living nearby are being advised to keep doors and windows shut. Three appliances and crews from Aylesbury, one from Amersham, one from Gerrards Cross, one from High Wycombe, one from Tring, one from Hemel Hempstead, the Incident Command Unit from Maidenhead and four officers are attending (more than 40 people in total)."