Officers are appealing for witnesses or information after thieves made off with a large number of sheep stolen from a field in Lindsey, Suffolk.
A police spokesman said: "Sometime between Friday, July 27 and Friday, August 3, offenders stole 27 ewes and 36 lambs from a field near the village.
"The ewes are described as Scotch Mules and the lambs are Texel Charollais crossbreds.
"Officers are keen to hear from anybody who may have seen either a suspicious vehicle or person in the vicinity during the time above. Anybody with any information is asked to call '101', quoting 44940/18."
Alternatively, those with information can contact the charity Crimestoppers anonymously on: 0800-555-111 or through their anonymous online form at: www.crimestoppers-uk.org.
Police would urge other livestock farmers to remain vigilant at this time and to call officers if they have concerns. If a crime is in progress always call '999'.