An arsonist broke into a car in Rushden before using petrol to set it on fire.
Police have launched an investigation after the incident at about 11.20pm on Sunday (August 18).
A BMW parked in Tennyson Road was set alight when a man broke its front passenger window and used fuel to set it alight.
A police spokesman said: "The offender is described as male, dressed all in back, short in height and of stocky build.
"It is believed he made off towards Highfield Road."
Anyone who saw the incident or has information about it should call Northamptonshire Police on 101.