London Zoo gorilla escaped through open cage door, reports suggest

Fury after 29-stone ape escapes from enclosure at London Zoo

Western lowland gorilla Kumbuka escaped from his enclosure in London Zoo (PA)

A leading wildlife group has called for an urgent inquiry into the escape of a large silverback gorilla from its enclosure at London Zoo.

The 29st dominant male ape Kumbuka escaped from his main enclosure on Thursday, with reports suggesting a cage door was accidentally left open.

London Zoo refused to be drawn on how the animal managed to escape, but said the gorilla had not smashed through any glass.The mammal made it as far as a non-public keeper area but the Born Free Foundation said it "could have ended very differently", calling for an inquiry into the incident.

Born Free also stated that the conservation benefits of keeping gorillas in captivity is “negligible at best”.

Chris Draper, associate director for animal welfare and care at the Born Free Foundation, told BBC Radio 4’s Today programme there is also little educational benefit from keeping animals like gorillas in zoos.

“The conservation benefits of keeping gorillas at zoos is negligible at best,” he said. “...The focus should shift away from keeping animals in captivity to looking at where the problems are actually taking places, habitat losses is accelerating at a ridiculous rate and we need to focus on where these animals have evolved to live,” Mr Draper added.

Visitors to ZSL London Zoo described fearing for their safety as they were ordered to take cover in buildings when the mammal got out of its den.

Malcolm Fitzpatrick, curator of mammals at ZSL, refused to specify how the animal managed to escape, despite persistent questioning on Radio 4's Today programme.

Mr Fitzpatrick said: "Categorically I can say that a male silverback gorilla Kumbuka did not break through any glass.

"Kumbuka got out of his back dens into a secure keeper area."

In a separate statement, the Born Free Foundation said the incident was a “startling reminder” of the risks of keeping dangerous wild animals in captivity.

“While we are relieved that this incident apparently ended without injury to visitors or to the gorilla, it is yet another startling reminder of the risks associated with maintaining dangerous wild animals in captivity,” Mr Draper said.

“This incident could have ended very differently. We are calling for an urgent inquiry into the circumstances surrounding this escape, and into safety procedures at London Zoo.”

Visitors at London Zoo were asked to take cover in buildings after a male ape, named Kumbuka, got out of its den.

Armed police were deployed and Kumbuka was eventually tranquillised and returned to its enclosure.

Kumbuka had remained in a secure keeper area and a zoo official said members of the public were “never in any danger”.

It is the second high profile case involving a gorilla in captivity after Harambe, a gorilla from Cincinnati Zoo, was fatally shot after a toddler climbed into his enclosure.