The Toronto Zoo is investigating after a video surfaced online appearing to show a woman jumping over a protective fence to recover a hat that fell inside a tiger's pen.

In the video posted on YouTube on Saturday, the woman can be seen climbing down the fence and reaching to grab the hat, while a tiger, separated by a second fence, lunges toward her.

After recovering the hat, the woman hops back over toward a group of onlookers.

"You're a moron, you're a moron," a man can be heard shouting. "You're a bad example to everyone else's kids."

Another woman can then be seen intervening to break up the argument.

"She jumped into a tiger cage. Are [you] kidding me?" the man can be heard saying in response.

Toronto Zoo spokesperson Jennifer Tracey told CBC News that she learned of the incident through the YouTube video and that the zoo is seeking witnesses who can help explain what happened.

"It was very irresponsible of this individual to jump over the boardwalk and [she] could have easily injured herself by exciting the animal in this way," Tracey said. "The situation could have been much worse."

No zoo staff were at the tiger's pen when the incident occurred, Tracey said.

The staff member assigned to the tiger's pen also watches over other animals in the Indo-Malayan area, such as snow leopards and the zoo's Indian rhino. According to Tracey, that staff member would have likely been at another pen when it happened.

"It's not unusual that visitors may drop things [inside an animal's pen], but when they do, they should notify zoo staff because they have the necessary equipment to help retrieve it," she said.