A crew from Crowborough Fire Station were called to a vehicle fire on Forest Dene in the early hours of Thursday 21st August.
When the fire engine arrived at the scene at about 12.45am a light commercial van was well alight.
Firefighters wore breathing apparatus and used a hose reel to tackle the fire.
There were no reports of injuries.
Sussex Police are treating the incident as an arson attack and Officers are investigating. They would to hear from anyone with information about the incident.