A viral video showing a man climbing into a zoo enclosure to sneak up on and spank a hippopotamus has sparked a police investigation.
The Los Angeles Times is reporting that the authorities are calling on the public for information to help locate the unidentified man at the centre of the bizarre clip.
In the footage, posted on Twitter, the man can be seen climbing a fence and approaching two hippos, before smacking one and making a quick escape.
The hippos have since been identified as Rosie and Mara.
Four-year-old Rosie was the one spanked in the clip.
While she didn't suffer any lasting or visible injuries, experts have warned that the incident may have caused stress issues for the animal.
The man involved was also lucky to escape the incident unscathed.
Hippos represent one of the world's deadliest large animals.
Known for their aggressive nature and sharp teeth, they kill around 500 people in Africa every year and can weigh anywhere up to three tonnes.
Despite the furore sparked, zoo spokesperson April Spurlock was keen to stress to the LA Times that it was likely to be "an isolated incident."
"Most people know not to go in with the animals. It's common sense," she added.