The last three elephants still in a traditional South African zoo entered their enclosure in single file, fruit and vegetables scattered on the ground to encourage natural foraging. For visitors to the popular Johannesburg Zoo, it was a chance to see Africa's largest land animal in real life.

But for animal welfare campaigners, it is a scene of cruelty that they have petitioned the courts to end by ordering the trio's release into a rewilding sanctuary. In a case supported by international elephant experts, the campaigners told a court in May that observation showed that Lammie, aged 47, Ramadiba, 28, and Mopane, 26, were distressed and depressed.

"These elephants are highly intelligent, socially complex and sentient beings who are living in conditions that are damaging to their well-being, and who are, as a result, in a state of distress," said the three parties behind the case.

The court should "authorise their immediate release to a suitable sanctuary... where they can rehabilitate", they argued. Judgment is expected in the coming weeks, said Megan Carr, senior researcher at the EMS Foundation that is part of the application.

Carr told AFP the three elephants were the only ones remaining in an urban zoo environment on the entire continent. "They are the last three elephants showcased within an exhibition in a traditional zoo-type setting in South Africa and Africa," she said.