A fire at a garage in Markyate was started deliberately, say Herts Fire And Rescue Service.
The blaze, which happened at the rear of houses in Corner Wood, was reported at 8.37pm on Monday night.
Retained crews from Markyate and Redbourn were sent to the scene to tackle the flames, and had put the fire out by 9.10pm.
The fire service also reported the suspected arson in the village to police, but investigators were not required at the scene.
Police spokesman Sarah Spence said: “The fire service informed us that they were dealing with a fire at a garage, but police were not requested.
“The cause of the fire is still being investigated by the fire service.”