An arrest has been made after a SECAmb ambulance was left in flames, and had to be extinguished by firefighters from West Sussex Fire and Rescue Service.
Sussex Police said it was called to the scene on Harlands Road in Haywards Heath at 4.08pm.
A 27-year-old man - who had been being assessed by the anbulance crew at the time - was arrested on suspicion of arson and remains in custody.
A South East Central Ambulance Service spokesperson said:
“We thank our police and fire colleagues for their swift actions in assisting us with this serious incident.
"We are very thankful that the crew, while shaken were uninjured.”