There’s an elephant in my yard    (April Fool's Day - 1960)

George Morris of Safford, Arizona woke to find a full-grown elephant eating lilies in his backyard. He assumed it had to be some kind of elaborate April Fool’s Day joke. It wasn’t. But when he called the police to report the animal to them, they initially refused to believe he was telling the truth. Finally they sent over some officers. It turned out that “Dumbo” had been accidentally left behind by a circus that had pulled up stakes the night before. The circus was notified and a van was sent to pick up Dumbo. [The Ada Evening News, Apr 3, 1960.]