In the movies Salman Khan always wins. But offscreen, the Bollywood tough guy hero may have met his match in a 530-year-old Hindu sect that puts animals above humans -- especially superstars.

The determination of the Bishnoi community forced Khan to spend two sleepless nights in a Rajasthan jail following his conviction last week for killing rare antelopes on a hunting trip.

The Bishnoi -- self-styled ecological guardians whose guiding principles forbid them to kill animals or even sterilise a bull -- have been pursuing Khan ever since a fateful night in October 1998.

Their testimony had seen the actor detained three times over the past two decades before his shock conviction last week.

The Bishnoi say Khan was seen killing two black buck antelopes while on safari in the Rajasthan desert, where most of the community live.

It was a grave sin in their eyes.

The black bucks are protected by law and the Bishnoi also consider the antelope reincarnations of their 15th century saint Guru Jambheshwar.

They believe their perseverance paid off. As Khan was ordered last Thursday to serve a five-year jail term, the Bishnoi set off firecrackers and danced in celebration.

After Khan was granted bail on Saturday, the Bishnoi said they would take the fight to the high court and even India's Supreme Court if needed.

"We are doing our duty," Ram Nivas Dhoru from the Bishnoi anti-poaching activist group, Bishnoi Tiger Force, told AFP.

"If you kill our children (wildlife), we will make sure you are brought to justice. It doesn't matter if you are Salman Khan or anyone else."

Poonamchand Bishnoi and Chhogaram Bishnoi, two Bishnoi villagers, told successive court hearings that they saw Khan and four other actors on a poaching mission.

Khan strongly denies killing the animals.

Bishnoi villagers say they heard gunshots in the night and found carcasses in the bush.

The two witnesses say they followed the actors' car on a motorcycle and took down its number, passing the information to the authorities.

The Bishnoi also alleged that Khan killed chinkaras, a Central Asian gazelle. Khan was convicted of the offence in 2006 and ordered jailed for five years. He spent a week behind bars before being granted bail but was acquitted ten years later.

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A way of life

The testimony of the Bishnoi was striking in a country where witnesses often become forgetful, or turn hostile due to fear and intimidation -- especially in high-profile cases.

The episode has strengthened the legend of the Bishnoi, who for centuries have devoted their lives to protecting animals and trees from hunters and loggers.

The Bishnoi trace their origins to Guru Jambheshwar, whom they consider an incarnation of the Hindu God Vishnu, and whose 29 founding principles they live by.

It includes a pledge not to kill any living creature.

Legend has it that 294 Bishnoi men and 69 women sacrificed themselves or were hacked to death in 1730 when they tied themselves to trees which a local king wanted to fell to build a new palace.

Today there are around two million Bishnoi spread across northern and central India, community figures say.

In the past two decades up to nine Bishnoi have been shot dead by hunters, the Bishnoi Tiger Force says.

The community say their name "Bishnoi" comes from their 29 guiding principles -- 20 is "bis" and nine is "noi" in their dialect.

"We have to follow our guru's orders and that means protecting trees and animals. That is the way of life for us," said Dhoru.

For centuries, he said, Bishnoi women have been known to feed and treat abandoned fawns like their own children.

Khan has maintained his innocence, saying he was framed by the state forestry department for publicity purposes. His lawyers argue that the black bucks died of natural causes as there was no evidence they were shot.

Dhoru urged the actor to come clean. "If you have committed a sin, own up to it and face the consequences, do not run away," he said.