The tourists piled into the bus, which took them through a series of gates into an enclosed, snow-covered field. Within minutes, the bus - modified so that a steel cage covered the windows - was surrounded by more than 20 Siberian tigers.
A Toyota Land Cruiser pulled into the enclosure and someone inside tossed out two live chickens that landed near the left side of the bus. Cameras clicked and blood splattered. Within seconds, the tigers had ripped the birds apart.
As inhumane as this scene from February might appear, it is just a small part of what happens each day at China's "tiger farms".
Sanctioned by the government but accused of routinely violating Chinese laws and international agreements, these farms exist mainly to breed and kill tigers for the marketing of pelts and tiger bone wine.
A visit by a reporter to China's two largest tiger farms, in the northern city of Harbin and in the southern city of Guilin, found animals in deplorable conditions. In both cities, merchants openly sold bone wine, despite a 1993 ban by China on bone products sourced from both domesticated and wild tigers.
China's treatment of tigers was pushed further into the spotlight last week, when 15 people in south China were arrested for killing at least 10 of the big cats.
According to a newspaper, the Nanfang Daily, the tigers were killed to provide entertainment and fresh meat for businessmen hoping to show off their wealth in the city of Zhanjiang, in Guangdong province.
Animal welfare experts say such incidents show the Chinese government has done little to enforce its 1993 ban on the trade in tiger bones, a requirement of the UN Convention on International Trade in Endangered Species, which Beijing has ratified.
"China's wildlife law has all kinds of problems," says Toby Zhang, a Chengdu-based researcher for Animals Asia Foundation, a nonprofit organisation. "It effectively encourages people to breed tigers and other animals and use their parts for commerce."
For decades, China has sanctioned and even subsidised captive-breeding programs of rare animals, largely to supply enterprises that manufacture traditional medicines. At scores of bear farms, for instance, workers harvest bile from domesticated bears to make potions that purportedly cure liver problems and relieve hangovers.
Until recently, Chinese officials argued that, with tigers facing extinction in China and many parts of Asia, tiger farms helped relieve pressure on wild populations.
Yet many wildlife experts say the opposite may be true. With the growth of the tiger bone market, wealthy connoisseurs reportedly seek products derived from wild tigers, thinking they'll be more potent. Meanwhile, copycat tiger farms have sprouted in Vietnam, Laos and Thailand, and wildlife organisations suspect those have made use of captured tigers to enrich the gene pool of their breeding stock.
"There no evidence that the trade in captivity-bred tiger parts has relieved pressure on wild tigers," says Debbie Banks, a wildlife campaigner with the London-based Environmental Investigation Agency, which produced a report on China's tiger farms last year.
"If you look around Southeast Asia, you will find that countries with tiger farmers have fewer wild tigers than those that do not."
The government's State Forestry Administration, China's version of a wildlife agency, started encouraging and underwriting tiger breeding farms in the 1980s. Since then, the number of captive tigers in China has grown from about 20 to as many as 6000, spread across scores of farms and zoos, according to the Environmental Investigation Agency.
Since the 1940s, China's wild tiger population has dropped from about 4000 to an estimated 20 to 50 animals.
According to state media reports, tiger bones in China fetch prices that top 14,000 yuan (NZ$2621) per kilogram. Prices for tiger bone wine, derived by steeping the bones in alcohol, start at about NZ$116 and can top NZ$926 per bottle.
On a February 16 tour of the Harbin Siberian Tiger Park, glass cases of bone wine could be seen on display, including bottles that had an image of tigers on them. None explicitly were labelled "tiger bone", a sleight of hand that allows the marketing of a banned product in China.
A subsequent phone call to the gift shop was answered by an employee who offered assurance the wine was indeed made from tiger bone. He said it was produced by Hengdaohezi Siberian Tiger Liquor Co, which is listed as having its plant in Mudanjiang, a city about 300km southeast of Harbin. A half-kilogram of the top-shelf product, he said, could be purchased for about NZ$538.
Some wildlife experts say it is only a matter of time before China closes its tiger farms. Peter Li, a consultant with the Humane Society International and a political scientist at the University of Houston, said that public opinion in China is rapidly turning against the exploitation of tigers, bears and other animals.
A huge outcry erupted in 2010, when 11 Siberian tigers reportedly starved to death at the Shenyang Forest Wild Animal Zoo in northeastern China. That and other incidents led the forestry administration to issue a statement against animal mistreatment, "utilising animals for performance and engaging in illegal animal products trade". But the abuses continue.
One of the more notorious animal farms is the Xiongsen Bear and Tiger Mountain Village in the southern city of Guilin, which a reporter visited in early March.
Like its counterpart in Harbin, the Xiongsen park is home to hundreds of tigers, and several could be seen with serious injuries, including one that had had its tail chewed through; the dead portion had been left dangling.
Tigers were also used in an indoor performance at the park's "Theatre of Dreams," which also featured bears, monkeys and goats performing tricks, as their handlers cracked whips above them.
The park, which once attracted hundreds of tourists daily, was nearly empty on this particular Saturday. A taxi driver told a reporter that very few visitors come anymore. Photographs are now banned within the park, and a guard was assigned to follow a trio of visitors to ensure none was taken.