A driver chased and tackled a vandal to the ground in Northampton before the offender got up and threatened the driver with a knife.
The incident happened in Wellington Street shortly before midnight yesterday (Monday, June 4), when the vandal smashed the passenger window of a parked car before reaching in and grabbing cash.
The driver, who was with the vehicle, challenged and chased the offender, tackling him to the ground. The offender got up and threatened the driver with a knife before making off towards The Mounts.
A spokeswoman for Northamptonshire Police today said: "The offender is described as black, aged 20 to 30, about 6ft, with a slim build.
"He had short black hair and was wearing a black T-shirt, black trousers and a yellow high visibility vest. He was carrying some garden cutters as well as a knife."
Witnesses, or anyone with information, are asked to contact Northamptonshire Police on 101. Alternatively, they can call Crimestoppers anonymously on 0800 555111.