Animal rights campaigners People for the Ethical Treatment of Animals (Peta) have called for a boycott of a new film about a real-life attempt to save animals from Belfast Zoo during the second world war.

Zoo, written and directed by Colin McIvor and starring Art Parkinson, Penelope Wilton and Toby Jones, is about a 12-year-old boy who rescues a baby elephant from the zoo during the Belfast blitz after the ministry of defence ordered them to be put down.

Peta’s UK branch has criticised the decision to use a live elephant. The organisation’s director, Elisa Allen, told the Irish Times: “Animals aren’t actors, and since today’s film-makers have access to computer-generated imagery, animatronics and other cutting-edge technology, there’s simply no excuse for subjecting animals to the risk of physical harm, the confusing environment of a production set – including bright lights and loud, scary noises – and the stress of training, travel and confinement.”

The film-makers had announced in 2016 that after a worldwide search they had recruited a three-year-old elephant called Nellie, a resident of African Lion Safari in Hamilton, Canada.

At that time, Zoo producer John Leslie said: “There was a whole debate over whether or not we should use computer-generated imagery to put an elephant on the screen, but we all felt if we could work with a real animal we should.”