Thieves have stolen 500 partridges worth about £2,000 that were being kept in a pen at a large farm in Surrey.
Surrey Police said the "unusual" incident happened between Monday evening and Tuesday morning at the farm in Haxted Road, Lingfield.
Officers said a vehicle was driven over cultivated land at the 400-acre site to reach the French red-legged partridges.
Anyone who has been offered French red-legged partridges for sale is urged to contact police.
Sgt Mike Simmons said members of the Country Watch scheme, which was set up to tackle rural crime, have been urged to report suspicious activity in rural and isolated locations.
He said: "This is a particularly unusual crime and we are appealing to people to remain vigilant."
He also appealed to anyone who visited the Edenbridge and Oxted show and saw something suspicious but thought nothing of it at the time to contact the force.
The Edenbridge and Oxted Agricultural Show was held on Saturday and Sunday at the Ardenrun Showground in Lingfield.