Firefighters extinguished a van on fire in Snailwell on Saturday night.
One crew from Newmarket was called to The Street at 9.45pm, where they found one small van well alight.
Firefighters used breathing apparatus and one hose reel to extinguish the blaze.
No-one was believed to have been injured.
A Cambridgeshire Police spokeswoman said police were investigating whether the fire was started deliberately. Call police on 101 or Crimestoppers on 0800 555 111.