Held every year, the Yulin Dog Meat Festival results in the slaughter of thousands of dogs, which are then served in some of the restaurants in this city in south China.

An international campaign to halt the killing keeps growing each year. Millions in Canada, the U.K. and the United States have signed petitions calling for China to end the festival, which is scheduled to start this year on June 21.

Yet it not just foreign activists who are working to stop China's dog meat trade. There are now millions of pet owners in the world's most populous country. Many are appalled by Yulin's continuing celebration of the eating of dog meat and by the uncertain manner in which the meat is obtained.

Unlike South Korea, another Asian country where dogs are consumed, China does not have any large-scale dog-breeding farms. A four-year investigation by Animals Asia, an advocacy group, found no evidence of such breeding facilities. "The vast majority of so-called "meat dogs" are in fact stolen companion animals and strays," says the group's 2015 report.

Theft of dogs is rife in Beijing and other cities as well as in the countryside. According to news reports, organized gangs often use poison darts to sedate and then steal pets and stray dogs.

In February, China was riveted by the story of a blind man whose Labrador guide dog stolen. After saturation coverage of the theft, the dog was mysteriously returned after 2 days.

Violet, a resident of Beijing, is one of many in China who have became active in animal rights partly because of the allegations of dog snatching. She asked that her full name not be used since the Chinese government frowns upon nearly all forms of organized activism.

Last year, Violet said she teamed up with others in monitoring the trucks that travel to Yulin, carrying dogs thought to be strays or stolen. She then attended the festival in Yulin, a city of roughly 600,000 people in the Guangxi Zhuang Autonomous Region.

"When you visit the festival, you can see thousands of dogs that are shipped there," said Violet. In her opinion, many of the dogs appeared to be stolen, since they appeared to be purebred, not the kind that would be strays.

Andrea Gung, a Taiwan-born animal welfare activist who now lives in California, agrees with Violet. Gung, who has twice visited Yulin, believes that dog-meat restaurants depend upon stolen animals. Owners of those restaurants, she said, are increasingly trying to shield themselves from the international spotlight.

"It used to be you could go to the festival and see dogs being killed right on the street" by restaurant owners, said Gung, who heads a California-based group called the Duo Duo Animal Welfare Project. "That is not true anymore."

Gung and Violet say that defenders of the festival aggressively confronted them when they paid separate visits to Yulin last year. Gung said restaurant owners accused her of disrespecting the city's cultural heritage, a claim that she rejects. While some people in China have eaten dogs for generations, said Gung, Yulin only started hosting its dog meat festival in 2010.

Repeated attempts to contact the Yulin city government and dog restaurants in the city were unsuccessful. In the past, however, the festival's supporters have defended themselves by questioning why killing canines for meat is any different than killing cows, pigs or other livestock. "It's a fair question," said Violet, who is a vegan. But she says there are reasons beyond animal welfare to end China's dog meat trade.

Studies have linked incidences of rabies in Asia to the trade and consumption of dog meat. People butchering and handling dogs are at risk of being infected.

In addition, the meat sold in dog restaurants is not inspected and could pose a risk to those who eat it. In 2008, the World Health Organization warned that consumption of dog meat might have contributed to an outbreak of cholera in Vietnam.

Several governments in Asia — including the Philippines, Taiwan and Thailand — have banned the butchering of dogs for meat. In China, there are no laws against the slaughter.

As the announced date for the Yulin festival approaches, activists have again launched a #StopYulin campaign on social media.

Gung said she has personally pressed central government officials to clamp down on China's dog meat trade, but so far, there's been no visible government action. "Everyone is aware of the problem," she said, "but no one wants to stick their neck out."

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