Pablo Escobar 166 'cocaine' hippos face Narcos-style mass culling by Colombia

A portion of the 166 hippos from a herd that belonged to drug lord Pablo Escobar in the 1980s will be culled in Colombia in an attempt to control their population due to concerns over them going feral.

Twenty would be sterilised, others would be sent overseas, and "some" would be put to death, according to Environment Minister Susana Muhammad.

For years, experts have attempted to manage the hippos' population.

Hippos were brought in by Escobar for his Hacienda Nápoles private zoo. When he was shot and murdered by police in 1993, they were free to wander.

Authorities have attempted a number of measures, such as sterilisation and sending some animals to other zoos, to slow down the population increase in the Magdalena, Colombia's main river.

Despite best efforts, the herd continued to grow unchecked because of the absence of predators and the rich, marshy Antioquia region, which created ideal circumstances for the native African mammal to flourish.

When hippos were classified as an invasive species last year, a slaughter became possible, sealing their doom.

"We are working on the protocol for the export of the animals," Muhamad was quoted as saying by local media.

"We are not going to export a single animal if there is no authorisation from the environmental authority of the other country."

She stated that as a last resort, the ministry was developing a policy for euthanasia.

Experts in Colombia have long cautioned that the unchecked breeding of hippos threatens both indigenous animals and people.

If nothing is done, the population is predicted to reach 1,000 by 2035. However, animal groups claim sterilisation causes pain for the animals and puts veterinarians at grave risk.

Male hippos can weigh up to three tonnes as adults, making them one of the largest land mammals. They rank among the deadliest as well, taking the lives of about 500 people annually.

There have been attacks on fishing communities along the Magdalena River, and some hippos broke into a schoolyard, but no one has been killed.

Heading the Medellín cartel, Escobar earned the nickname "cocaine king" and acquired an estimated wealth of $30 billion (£25 billion) by transporting drugs into Miami and the southern United States.

During his more than ten-year reign of terror, he was involved in kidnappings, hundreds of killings, bombings, bribery, turf conflicts with rival drug lords, and a brief stint as an elected politician.

One of the world's most wanted individuals, he surrendered to Colombian police in 1991 on the understanding that he would be housed in the prison he had constructed, La Catedral, for five years.

A year later, despite efforts by the government to transfer Escobar to a more secure prison, he went on the run.

In his hometown of Rionegro, he was shot and killed on a rooftop on December 2, 1993, while attempting to elude the authorities, earning him a $2 million US bounty on his head.

In addition to leaving a 5,500-acre private citadel in Antioquia called Hacienda Nápoles, he also left behind a history of violence and a menagerie that included four hippos, giraffes, camels, and zebras.

Following Escobar's death, the government turned over the property to impoverished residents, and the hippos were allowed to roam freely because they were thought to be too hard to capture.