Intruders entered a farm in Bexhill and stole up to 2,000 litres of red tractor diesel, according to police.
The incident took place at a farm in Sandhurst Lane, Bexhill, on Wednesday (March 6).
Anyone with information is asked to contact police, quoting reference 0619 06/03.
Elsewhere in Rother, three wood burners were stolen from an outbuilding on a farm in Ewhurst in Robertsbridge, according to police.
Witnesses to the incident on Friday should contact police quoting 0355 08/03.
Another farm in Robertsbridge was entered last Monday.
Intruders forcefully broke into 18 storage containers at the farm on the A21 at Johns Cross.
Police do not have a list of what had been stolen at this time, but asked anyone with information to contact them quoting 0247 04/03.
A police spokesman said: "If you saw or heard anything, or have any information about any incident please contact us online, email us at firstname.lastname@example.org or call 101, quoting the reference number provided.
"Alternatively you can contact the independent charity Crimestoppers, anonymously, on 0800 555 111, or online at www.crimestoppers-uk.org."
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