They found the owners - who came twice for the animal and said they would be back again - but never returned.
Oreo is now in holding at the Durham Animal Protection Society. If the owner abandons the animal, then the horse legally has to be auctioned off.
If the owner surrenders it, then it could be adopted, or, there's another solution the sheriff's office is hoping for.
"We would ask that the owner come and retrieve Oreo and everyone goes about their way. But there's obviously something else going on. Maybe the owner can't afford Oreo anymore, doesn't want Oreo anymore, and that's fine. But if that's the case, let's maybe see if that owner would be willing to surrender Oreo and then we can find Oreo a new home," explained Deputy Paul Sherwin with the Durham Sheriff's Office.
If the owner surrenders the horse, Animal Protection says they have several rescue groups interested in him so they're hoping that will be the outcome.