"I knew that somebody had to have taken them because there's no way that they can get out of the building," said Gretchen Crowe, animal caretaker at Special Memories Zoo, to ABC News, even though the shed wasn't locked.
The Outagamie County Sheriff's Office was informed of the missing animals on Thursday and is doing everything it can to find the animals, but the owner of the zoo, Donna Wheeler, fears the worst - that the vulnerable baby kangaroo could be dead already.
Lieutenant Terry Hammen, who is heading the investigation, told The Dodo that the Sheriff's department is reaching out to everyone he can to get information about where the animals could be.
"We're reaching to outside agencies and using social media to get the message out there. We're hoping people will report anything that's suspicious, anything that has to do with exotic animals, or anyone acting odd or posting photos of these animals," Lieutenant Hammen said, adding that, while animals have been stolen from farms in the area before, in his twenty years in the department he's never had a case like this.