Gibbon's zoo enclosure escape caught on camera

July 25 (UPI) -- A visitor to a South African zoo captured video of a gibbon that escaped from its enclosure and climbed free on the outside of the primate cage.

The video shows the gibbon perching on the railing that prevents zoo visitors from coming to close to the large cage housing the gibbons at the Johannesburg Zoo after it somehow slipped out of the enclosure.

The gibbon then climbs the exterior of the enclosure and moves around it before disappearing out of sight.

"What a surprise to see one of them swinging on the outside of the cage," the filmer wrote. "The security people called the vet but unfortunately we could not wait to see how and what they did to get him back in the closure."