A life-size bronze cast of a famous gorilla is expected to sell for thousands of pounds when it goes under the hammer, according to auctioneers.

Jambo hit the headlines for guarding a five-year-old boy who fell into his enclosure at Jersey Zoo on July 31 1986.

The gorilla was credited with changing public perception of silverbacks from dangerous King Kong beasts to gentle giants and went on to become immortalised in bronze by sculptor David Cemmick.

The cast will be sold at Dominic Winter Auctioneers in South Cerney near Cirencester, Gloucestershire, next month, with a pre-sale estimate of up to £20,000.

The boy, Levan Merritt, was knocked unconscious on landing in the gorilla enclosure.

His mother watched as Jambo walked towards Levan, sat down beside him and, as if guarding him from the other gorillas, stayed with him and stroked his back until Levan was rescued by the emergency services. The cast was based on a drawing by Mr Cemmick, who visited Jersey Zoo to sketch Jambo and the other gorillas in 1987.

Mr Cemmick went on to work with mould-maker Sebastian Wylder to create the cast.

Nathan Winter, from Dominic Winter auctioneers, said: “We are thrilled to have such a magnificent and rare sculpture of such historical importance as part of our auction.

“Jambo was renowned for changing the public’s perception of gorillas back in the 1980s and this unusual life-size cast is a remarkable original work.

“We believe that there will be much demand amongst nature enthusiasts and art lovers to buy this piece of history.”