KRUGER NATIONAL PARK, South Africa — They definitely did not look like ordinary big-game hunters, the stream of slender young Thai women who showed up on the veld wearing tight blue jeans and sneakers.
But the rhinoceros carcasses kept piling up around them, and it was only after dozens of these hulking, relatively rare animals were dead and their precious horns sawed off that an extravagant scheme came to light.
The Thai women, it ends up, were not hunters at all. Many never even squeezed off a shot. Instead, they were prostitutes hired by a criminal syndicate based 6,000 miles away in Laos to exploit loopholes in big game hunting rules and get its hands on as many rhino horns as possible — horns that are now literally worth more than gold.
''These girls had no idea what they were doing," said Paul O'Sullivan, a private investigator in Johannesburg who helped crack the case. "They thought they were going on safari."
The rhino horn rush has gotten so out of control that it has exploded into a worldwide criminal enterprise, drawing in a surreal cast of characters — not just Thai prostitutes, but also Irish gangsters, Vietnamese diplomats, Chinese scientists, veterinarians, chopper pilots, antiques dealers and recently a U.S. rodeo star looking for a quick buck who used Facebook to find some horns.
Driven by a common belief in Asia that ground-up rhino horns can cure cancer and other ills, the trade has also been embraced by criminal syndicates that normally traffic drugs and guns. They have branched into the underground animal parts business because it is seen as "low risk, high profit," U.S. officials say.
''Get caught smuggling a kilo of cocaine, you will receive a very significant prison sentence," said Ed Grace, a deputy chief with the U.S. Fish and Wildlife Service. But with a kilogram of rhino horn, he added, "you may only get a fine."
A risk of extinction
The typical rhino horn is about 2 feet long and 10 pounds, much of it formed from the same substance as fingernails. Yet it can fetch nearly $30,000 a pound, more than crack cocaine, and conservationists worry that this price could drive rhinos into extinction.
Gangs have even smashed into dozens of glass museum cases across Europe to snatch them from exhibits.
U.S. federal agents recently staged a cross-country undercover rhino-horn sting operation, called Operation Crash, "crash" being the term for a herd of rhinos.
Among the 12 people arrested: Wade Steffen, a champion steer wrestler from Texas, who pleaded guilty in May to trafficking dozens of horns that he found through hunters, estate sales and Facebook; and two members of the Irish gang suspected of breaking into the museums.
In South Africa, home to most of the world's last 28,000 or so rhinos, the government is struggling to stop the slaughter, employing thousands of rangers, the army, a new spy plane, even drones. But it is losing.
The number of rhinos poached in South Africa has soared from 13 in 2007 to more than 630 this year. The battleship-gray animals are often found on their knees, bleeding to death from a gaping stump on their faces.
Kruger National Park, an enormous wildlife refuge in South Africa's northeast, is where many rhinos are being poached. The park borders Mozambique, a poor country scarred from years of civil war. Park rangers say Mozambican gunmen pour through Kruger's chain link fences, downing rhino left and right.
Some sophisticated poaching rings use helicopters to spot the animals and veterinarians to dart them with tranquilizers. Others don women's shoes, to leave misleading tracks.
''At any one time, there are up to 10 groups operating inside the Kruger," said Ken Maggs, a South African National Parks official. "These guys are trying new methods daily."
Rhinos long valued
Scientists say that maybe 1 million rhinos once roamed the earth, and for some reason, humans have been fascinated with the horn for ages. The ancient Persians thought rhino horn vessels could detect poisons. The Chinese thought rhino horn powder could reduce fevers. The Yemenis prized the horn for coming-of-age daggers, presented to teenage boys as a sign of manhood.
In Asia, faith in traditional cures runs strong, fueling demand as Asian economies grow, though there is no scientific proof rhino horn can cure cancer.
In 2008, a Vietnamese diplomat in South Africa's capital, Pretoria, was caught on camera receiving rhino horn — in the parking lot of the embassy. Around the same time, a Chinese company opened a secretive rhino breeding center in China's Hainan province, reportedly to produce rhino-based medicine.
In the past 50 years, the overall rhino population has plummeted by more than 90 percent, despite an international ban on the trade in rhino parts since 1977.
But in South Africa, it is legal to hunt rhinos, creating the loophole for the Thai prostitutes. Hunters must agree not to sell the horn set (rhinos have a large front and smaller back horn), and hunters are allowed to kill only one white rhino every 12 months. (Black rhinos are critically endangered and very few are hunted in South Africa.)
South African law enforcement officials say gang leaders in Thailand and Laos decided to enlist Thai prostitutes who were already in South Africa with valid passports and use them to obtain hunting permits. The women then tagged along on the hunts, often dressed in catchy pinks and blues, but somebody else — usually a professional hunter — pulled the trigger.
''I don't know whose idea it was to use the ladies, but it was a … good one," said O'Sullivan, the private investigator.
None of the two dozen or so prostitutes involved have been prosecuted — the intent was to get the big fish. So O'Sullivan leaked a photo of an enormous stockpile of ivory and rhino horns to one of the women, along with a message for her boss, a bespectacled Thai man named Chumlong Lemtongthai, that everything was for sale: "I wanted the big man himself to come here and negotiate."
Lemtongthai did exactly that, and he was arrested soon after. He pleaded guilty and was sentenced in November to 40 years.
''I do not want to see a situation where my grandchildren will only be able to see rhino in a picture," said the judge, Prince Manyathi.