A Thai tycoon accused of killing a black leopard was sentenced to 16 months in jail on other poaching-related charges Tuesday but allowed to go free pending an appeal, in a case that has caused an outcry in a country fed up with impunity for powerful figures.

Premchai Karnasuta whose company is behind major infrastructure projects such as Bangkok's monorail and its airport, was arrested by rangers in a national park in February 2018.

AFP

He and three others were detained after rangers stumbled upon their campsite and found guns and animal carcasses, including a Kalij pheasant, a red muntjac - or barking deer - and the pelt of a black leopard.

While Premchai was found not guilty of possessing a leopard carcass, he was convicted of three other poaching-related charges.

The verdict, handed out in a statement to reporters waiting at the Thong Pha Phum courthouse, said Premchai was "sentenced altogether to 16 months".

Two others caught with him - his driver and cook - received lesser sentences, while his hunting guide was sentenced to three years and five months.

A court official said the tycoon was immediately released on bail of 400,000 Thai baht ($12,600) as he was not considered a flight risk.

Thai courts sometimes grant bail immediately to a convicted person in the expectation they will appeal, and Premchai's lawyer later confirmed he would challenge the verdict.

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The sentence comes less than a week before a general election on March 24, the first polls since the military seized power in 2014 vowing to expunge graft and uphold the rule of law.

After Premchai's arrest, the striking images of the skinned leopard went viral, inspiring protests that saw demonstrators don black leopard masks, as well as graffiti of the cat across city walls and a Change.org petition calling for an investigation.

Park ranger Vichaen Chinnawing, who arrested the businessman and has been hailed as a hero in Thai media, said he was satisfied with the conviction.

"I have done my best in this case. If the soul of the dead leopard knows, it will be grateful," he told AFP.

Arrests and convictions for poaching happen often in Thailand but they are rare when it comes to prominent individuals.

"Justice is meted out unequally," said Steve Galster of Freeland Foundation, a wildlife NGOwhich works with Thai forest rangers, adding that he hopes the court "will stick with the decision" after Premchai's appeal.

"The main thing is this is a public shaming for Premchai," he said.

Thai media followed every detail of the case, including the authorities' investigation of human faeces found at the scene and a raid on Premchai's home where police uncovered a stash of ivory and guns.

AAP

Premchai is the president of the publicly traded Italian-Thai Development, a Bangkok-based company that helped build Thailand's Suvarnabhumi airport and the city's skytrain public transit system.

Although he was listed as one of Thailand's 50 richest people by Forbes in 2016, he dropped off the list the following year as the government delayed infrastructure spending.

As Premchai was leaving the court following his sentencing and bail, reporters asked him to comment.

"I'm sorry," he said, before he was ushered into his car.