It remains one of the strangest conundrums in modern zoological history – what to do with the descendants of Pablo Escobar’s hippos?

The animals – herbivores native to sub-Saharan Africa – were originally imported into Colombia by the drug kingpin for his own entertainment. But the beasts and their offspring were left to roam free after his death in 1993.

Now, the expanding population of feral hippopotamuses have become such an environmental blight, they are facing a mass extermination by the authorities.

Yet they may have found an unlikely stay of execution, after they were offered shelter in India by the son of a billionaire.

Anant Ambani, the son of Indian tycoon Mukesh Ambani, has revived an earlier offer to bring the 80 hippos to his Vantara animal sanctuary, in the state of Gujarat, to save them from death.

Ambani said that as the hippos were “living, sentient beings … if we have the ability to save them through a safe and humane solution, we have a responsibility to try”.

But Vantara is shrouded in controversy. Home to more than 150,000 animals, including many endangered species, it has faced allegations of illegal and unethical sourcing of its inhabitants. The international watchdog Cites (convention on international trade in endangered species) has flagged alleged noncompliance with wildlife trade rules.

Some critics have accused the sanctuary of indirect complicity in wildlife trafficking, while others have condemned Vantara as an Ambani family “vanity zoo” – the public do not have access. The project is also seen to have weighty political backing, and it was relaunched by the Indian prime minister, Narendra Modi, himself.

The Ambani family and Vantara deny the allegations and an investigation last year by the supreme court of India found no evidence of wrongdoing.

A similar plan to bring 60 of the Colombian hippos to the sanctuary, when it was formerly known as Green’s rescue and rehabilitation, was first proposed in 2023.

However, the logistical problems of capturing and moving the hippos, which live in the wild and weigh roughly two tonnes each, as well as matters concerning permits and the inter-governmental organisation involved, appear to have prevented the animals from making the journey to India.

This time, a statement by Ambani said he had directly appealed to the Colombian government to allow the “safe, scientifically led translocation that would bring the 80 animals to a permanent home”.

“These 80 hippos did not choose where they were born, nor did they create the circumstances they now face,” he added.

It would be no small feat to ship the hippos to India and would probably come with a hefty price tag, possibly more than $4m (£3m).

Should they make it to Gujarat, it would add another twist in the adventures of Escobar’s hippos.

It was back in the 1980s that Colombia’s most famous drug lord brought four hippos from sub-Saharan Africa to join the zoo on his Hacienda Nápoles, which also included elephants and giraffes.

After Escobar died in a special forces raid in 1993, the authorities left the hippos – which are dangerous and difficult to control – to run wild. Over the years, they made their home on the Magdalena River basin, where their population exploded due to a lack of predators and abundant food.

According to recent estimates, there are more than 200 hippos roaming free, the largest population outside Africa and one of Colombia’s greatest environmental menaces. They have destroyed vegetation and terrorised and killed local animals and livestock. So far, efforts to sterilise them have not worked fast enough.

As experts warned their population could reach more than 1,000 in coming decades, Colombian authorities announced this month that the hippos would begin to be formally hunted and culled to bring their numbers under control – an announcement that sparked outrage from animal rights campaigners.

Questions remain over the suitability of Vantara for the boisterous, mud-loving animals.

Hippos are not native to India and, while the sanctuary hosts bears, crocodiles, elephants, leopards and tigers, they do not publicly have any record of homing a hippo – let alone 80 of them.

However, Ambani insisted that his sanctuary would give the Escobar hippos the safe home they needed. “Vantara has the expertise, infrastructure and resolve to support this effort, entirely on Colombia’s terms,” his statement added.