The rhinoceros endemic to Indonesia’s most populous island is critically endangered, with authorities believing there are only around 82 remaining in Ujung Kulon National Park in western Java — their last stronghold.

In 2023 authorities uncovered a criminal gang that confessed to killing 26 rhinos over the span of five years in the 120,000-hectare park.

A court in Indonesia’s Banten province this week sentenced the mastermind of the gang to 12 years in prison and gave five of his co-conspirators 11 years, according to rulings posted on its website.

All were also fined 100 million rupiah ($6,135) each, which would be replaced by three additional months in prison if not paid, said the rulings issued on Wednesday.

“It sets a strong precedent and delivers a clear warning to those who would threaten Indonesia’s wildlife,” Nina Fascione, Executive Director of the International Rhino Foundation, said in a statement Friday.

“Adequate justice in a case like this is critical to ensuring rhinos are safe from future poaching.”

Irfan Suryana, a representative of an environmental collective based in villages around the national park, welcomed the punishments but said more needed to be done to prevent poaching.

“For many [of the poachers], such actions are often driven by economic hardship. Our responsibility is not only to prohibit such actions but also to provide education and raise awareness,” he said.

‘Break the chain’

Authorities paraded the poachers last year, saying most of the rhinos were killed for their horns, which were sold on to dealers in China.

The horn is ground down to be used in traditional medicines, but scientists say it has no proven qualities.

Ujung Kulon National Park chief Ardi Andono told AFP Friday the sentences were the highest punishment possible for poaching in Indonesia.