Firefighters were called to a car park in Crabb Street, Rushden, at about 5.30pm on Monday, June 3, after a van caught on fire.
The engine compartment and passenger area of the Citroën Berlingo was severely damaged by the fire.
Some slight damage was also caused by heat to an adjacent Peugeot car.
One fire crew from Wellingborough attended the scene.
A spokesman for the Fire and Rescue service said the cause was accidental.