The opportunity to hunt an endangered African black rhino in Namibia went to the highest bidder over the weekend. Wealthy U.S. and foreign hunters gathered at a Dallas convention center on Saturday, or joined by phone, to participate in the Dallas Safari Club’s auctioning off of a permit to kill a black rhino, something the club has maintained was done in the name of “conservation.”

According to multiple sources, including CNN, the permit sold for $350,000, although the club previously stated the permit could go for as much as $1 million. The hunter who bought the permit during the closed-door event was not named and could be from anywhere in the world.

According to The Associated Press, dozens of protestors showed up outside the convention center on Saturday to protest what became a controversial public sale, one that even involved death threats being sent to members of the Dallas Safari Club after the club announced last year it would be auctioning off a black rhino hunting permit. Saturday’s auction marked the first time a permit of this kind was sold outside of Namibia, which grants five permits a year to hunt a black rhino as part of the African country’s culling measures.

The Dallas Safari Club has said all the proceeds from the sale of the permit will go to the Conservation Trust Fund for Namibia’s Black Rhino. Ben Carter, the Dallas Safari Club’s executive director, said the permit sale’s objective is to help protect the African black rhino population.

“First and foremost, this is about saving the black rhino,” Carter told AFP. “There is a biological reason for this hunt, and it’s based on a fundamental premise of modern wildlife management: Populations matter; individuals don’t. By removing counterproductive individuals from a herd, rhino populations can actually grow.”

His view is that by removing certain individuals – usually older rhinos whose breeding years are over – younger, more virile males are allowed to reproduce. Older male black rhinos tend to be extremely territorial and will sometimes charge and kill younger ones.

Still, animal-rights activists say hunting male rhinos, especially for sport, to conserve their population isn’t the way to go.

"Shooting a rhino is about as difficult as shooting a tank," Wayne Pacelle, president of the Humane Society of the United States told ABC News last October. "In terms of the sportsmanship component, it's totally lacking."

Critics say the auction sends a negative message to the public: that killing an endangered African animal is a sport. Animal- rights groups chastised the club for selling the permit, calling the hunt’s endorsement as a conservation tool “perverse” and “a sad joke.” Online petitions demanding the auction be called off surfaced quickly on the Internet.

"This auction is telling the world that an American will pay anything to kill their species," Jeffrey Flocken of the International Fund for Animal Welfare, one of the largest animal-welfare charities in the world, told AP. "This is, in fact, making a spectacle of killing an endangered species."

Fifty years ago there were about 70,000 black rhinos in the world. Today there are just under 5,000 black rhinos left in the wild, and a third of those live in Namibia. Poachers have long targeted all rhino species, whose horns are extremely valuable on the international black market. Habitat loss has also led to the steep decline in Africa’s black-rhino population.