Visitors at the London Zoo were subjected to a scary experience when a silverback gorilla escaped its pen. While details remain uncertain why the incident happened, witnesses say that the silverback was able to escape by smashing through a glass panel at the end of its enclosure.

A statement released by the zoo said that the 18-year old gorilla, named Kumbuka, has been on the loose at the zoo for 25 minutes before staff managed to de-escalate the situation. They added that tranquilizers have been used to subdue the animal, said the Daily Mail.

London Zoo Gorilla Seen As Agitated Before Breaking Out

It seems that prior to escaping, visitors saw the silverback acting agitated. Officials are investigating the incident - how the gorilla escaped its pen and what possibly triggered its aggressive behavior.

Fortunately, there were no visitors or staff members harmed amidst the panic. Shortly after escaping, sirens have been heard inside the establishment and zoo-goers were instructed to remain indoors while the situation is being handled.

Three police vehicles quickly responded to maintain order and a helicopter was spotted overhead to provide an aerial view for the staff looking for the escaped silverback, according to the Mirror. Malcolm Fitzpatrick, the zoo's curator of mammals, said that the police are part of the establishment's procedure whenever something like this occurs.

Kumbuka Is Doing Well And Will Be Given His Favorite Treats

The incident happened on Thursday, late afternoon. Fitzpatrick said that while Kumbuka did manage to escape, the silverback only got to a secure keeper area and never ventured into parts of the zoo where about 100 visitors were staying.

"He was tranquilized at about twenty to six and back in his den by twenty past six," said Fitzpatrick. "I'm happy to report he's actually up and grumbling and interacting with the rest of his gorilla family."

Latest news on the matter said that Kumbuka is now in stable condition and will be given his favorite watermelon treats later. Animal lovers breathed a sigh of relief that the incident didn't end up like the one that occurred in Cincinnati zoo when a silverback was shot dead after a four-year-old boy had fallen inside a moat.