Two tortoises were stolen from a farm enclosure.
Joey, a bell’s hinge-back, and Phoebe, a serrated hinge-back, disappeared from Lee Valley Park Farm's Critter Corner in Stubbins Hall Lane, Waltham Abbey, between 1.30pm on Saturday and midday on Sunday.
The species, which hails from Africa, are smaller than the more-common Mediterranean counterparts, with Joey and Phoebe currently about the size of a mango.
Kate Chaplin, duty manager at the farm, said: “Although you can’t lean in to their enclosure and the door to it is latched shut, it is not locked, so we presume someone unlatched it and went in.”
Hinge-backs are not common pets due to the specialist care and environment required to keep them, but can be bought for around £25.
The animals are micro-chipped. meaning if scanned by a vet can be identified.
But so far no one has come forward with information.
The Critter Corner attraction had two Mediterranean tortoises returned to them anonymously after a theft about four years ago.
Lee Valley Park Farms Manager, James Broomfield said: “These animals require a special diet and a humid, heated environment and we’re very concerned about their well-being.
“The pair who lived in the Critter Corner area are presumed stolen and we would ask if any member of the public knows anything about their whereabouts to please contact Essex Police.”