Burglars broke in through the roof of an agricultural building in a Daventry village.
The break-in happened at an agricultural warehouse in Charwelton Road, Preston Capes sometime between 7pm on Sunday March 13, and 7am today Monday March 14.
The offenders broke into the property through the roof, causing considerable damage. After searching the offices, they stole keys to a lorry, which was not itself taken, and fuel from the diesel store.
Police believe the offenders would have made a lot of noise while breaking into the building and are appealing for witnesses, or anyone who may have seen or heard anything suspicious in the area overnight, to contact them.
Witnesses, or anyone with information, are asked to call Northamptonshire Police on 101.
Alternatively, they can call the independent charity Crimestoppers anonymously on 0800 555 111 or use the anonymous online form at www.crimestoppers-uk.org.