Subscribe | UPI Odd Newsletter Subscribe March 6 (UPI) -- A North Carolina animal sanctuary said someone broke into the facility and stole three rare river otters from their enclosure. Officials with the Animal Ed. Ventures sanctuary, which takes in former pets, said the otter enclosure and sanctuary gates were found open Tuesday morning, despite having been double-checked Monday night. Advertisement The river otters, named Sigmund, Nessy and Ned, were found to be missing. "The latch to their enclosure was completely intact," sanctuary director Corey Freeman told WTVT-TV. "There was no failure. This is a latch that can only be manipulated manually with a level of dexterity." Freeman said a high-pitched sound was heard in the area of the sanctuary about 2 a.m. Tuesday. "We don't know if this is motivated by money, we don't know if this was motivated by an extremist group that feels like all animals should be free," she said. "Are they being properly cared for? Does this person even know what they eat and what they need? They're not a creature that you can just put in a cage.... It's devastating." The Harnett County Sheriff's Office is investigating the otters' disappearance. Advertisement Read More Baby bear escapes wildlife rescue in Georgia Marijuana smokers find tiger in vacant Houston home Wolverine on the loose after Quebec zoo escape Escaped goat-antelope recaptured at British zoo