A thief assaulted two men who confronted him after he stole tools from a parked van in Bugbrooke.
On Tuesday (February 12), the man took the tools from the vehicle while it was parked in St John's Road and put them in another van.
He then assaulted two men who approached and challenged him, before driving away.
CCTV images of the man have since been released.
The man, or anyone who recognises him, is asked to contact Northamptonshire Police on 101. Alternatively, they can call Crimestoppers anonymously on 0800 555111.