Tens of thousands of people follow him on social media and, just before he flew out to Yulin, Hollywood stars inclu­ding Joaquin Phoenix, Matt Damon and Minnie Driver recorded a powerful video appeal in support of his work.

WARNING: This video has graphic content that may be disturbing to some viewers

Afterwards, donations poured in as Ching – wearing his trademark jeans and T-shirt – posted a video of himself pulling dogs out of a Yulin slaughterhouse, garnering more than one million Facebook views. The operation had, it seemed, saved animals’ lives, drawn the world’s attention to the dog-meat trade – and raised Ching’s profile.

Months later, however, and the Yulin rescue was being seen in a somewhat different light, as details emerged of a shambolic rescue that ended with between a half and two-thirds of the dogs dead and bitter recriminations between Ching and some of the volunteers who flew out to help him. The rescue has also triggered a fierce social-media debate in animal-welfare circles about Ching’s approach, his claims of routine torture and the implications of paying slaughter­houses to hand over dogs.

Although Ching has been widely credited with rescuing the 1,000 dogs by himself, two-thirds of the animals were paid for by two Buddhist organisations, which took the animals off to their own sanctuaries. Unknown to Ching, those dogs were fed and watered but denied life-saving injections and medical treatment, because of Buddhist beliefs. As a result, many of the already sick animals died of distemper and other diseases within days.

Ching’s charity had set up only one shelter, in Nanning, which was capable of taking in a maximum of 200 dogs. As well as the Buddhist groups, he had to seek help from the Humane Society International, which took 120 dogs to care for in its shelters in northern China. To complicate matters, Ching flew back to the US soon after the rescue, leaving behind a bemused and disorganised group of volunteers as reports began filtering through of mass deaths at one of the Buddhist sanctuaries.

The chaos deepened in the weeks that followed, as Ching accused American businessman Jeffrey Beri, a volunteer who had been put in charge of running the Nanning shelter, of mismanagement.

Beri, who has been travelling to and from China on business for 25 years, says he volunteered to help Ching after coming across his website: “I watched one of his videos and I dropped to my knees. I knew nothing about these atrocities that were taking place. I said, ‘This man is my hero. I’m going to help him out.’”

In August, though, Ching, who on his website questioned Beri’s “suspiciously high expenses”, cut off funds to his erstwhile admirer. Ching then arranged midnight raids on the Nanning facility, in which about 100 dogs – some already lined up with adoptive homes in the US – were snatched and taken to another shelter, some 700km away, in Changsha, Hunan province.

Ching is now embroiled in an exchange of legal letters, accusation and counter-accusation with Beri. After falling out with Ching, the 52-year-old has stayed on in China at his own expense, preparing the dogs left in his charge for export to new homes in the US – a relocation now being funded by Thailand-based charity Soi Dog Foundation. The last of those 71 dogs should have arrived in the US by the end of this month.

Beri says Ching’s decision to share the dogs with the Buddhist monks was “reckless”.

“The monks stopped the dogs from being brutally tortured but how should a dog die? In a cage suffering for a month from disease or neglect or in a slaughterhouse?” he asks.

“We thought the rescued dogs were all going to a safe house in Nanning,” says a female volunteer from the US who was with Ching throughout the rescue, and who asks to be named only as Sarah because of the abuse and threats she says she has received from Ching’s supporters. “Instead, 700 of them ended up at Buddhist sanctuaries and most died because they didn’t get the care they needed. If they had been left in the slaughterhouses to be hit on the head and killed, it would have been better than the suffering they went through.”

Sarah says Ching told her and other volunteers to leave on June 23, but she stayed to care for the desperately ill dogs in Nanning.

“He says most of the dogs are so sick they will die,” she says. “But I can tell you that of the dogs given care, 90 per cent will survive. For those not given care, 90 per cent will die.

“We didn’t let the dogs die and now he has to deal with that. His answer was to take them to an undisclosed place and adopt them locally, which is a death sentence. It puts them back in the market they were in.

“Marc has raised awareness of the dog-meat industry but at a great cost to dogs themselves,” Sarah says. “I was led to believe we were going over to rescue the dogs, give them proper medical care and place them in homes.”

Briton John Dalley, founder of the Soi Dog Foundation, says he has serious concerns about Ching’s tactics. He recalls how Ching visited his Phuket headquarters on one of his solo missions, three months before the Yulin rescue, and adopted a dog that had had its paws severed. It was later claimed on Ching’s website that the dog had been rescued from the dog-meat trade.

“I told him repeatedly those dogs were not from the dog-meat trade but from road accidents and cruelty cases in Phuket,” Dalley says. “He knew very well but when I chal­lenged him about it, he said, ‘I must have misunderstood.’”

Asked about the incident, Ching responds that the error was made by his assistant, Valarie Ianniello, and was correct­ed as soon as Dalley pointed it out.

Dalley also raises questions over the shocking video clips from Asia used by Ching in his fundraising appeals. The clips show dogs being hung by the neck, dogs with their paws hacked off and a dog being strung up by the neck in a public park in Indonesia, yelping as it is blow-torched.

“I don’t understand how anyone who professes to be in animal welfare can film that sort of thing without intervening,” Dalley says, adding he has asked Ching for details of where and how the videos were filmed but has received only vague and contradictory responses. “For God’s sake, he could have intervened and saved those dogs. But it seems to me the ones he claims to save are after they’ve been tortured or abused.”

Other animal-welfare veterans in the region are uneasy with Ching’s claims that dogs in Asia are tortured for up to 40 hours before being killed, saying it does not reflect the reality of a trade in which dogs are usually dispatched brutally but swiftly, for practical reasons. Ching’s posts stoke anti-Asian feelings among people who respond to his appeals, they argue.

SPEAKING BY TELEPHONE from California, Ching admits to having made mistakes with his Yulin rescue but says he set out with the aim of shutting down slaughter­houses, not saving dogs, and had to improvise and seek help from other groups when he found himself with hundreds of dogs on his hands. He accepts that hundreds died but claims that he at least gave them a chance.

“All of those dogs were supposed to die,” Ching says.“If you had a chance to stay alive and fight for your life so you could have a family and love would you choose that? Or would you just choose to die a terrible death and your life ends right there? I think 100 per cent of the world would choose to take that chance.”

He admits he “didn’t know the philosophy of the Buddhist monks” and hadn’t realised the dogs would not be given treat­ment or injections. He says his team paid for vets to help treat the dogs in the sanctuary when they found out what was happening.

Asked why he returned to the US so soon after the rescue, when the fate of so many dogs was in the balance, he says, “emotionally I was unfit. It was [the effect of] having to watch all these dogs in distress. It is heartbreaking. Some people are strong and can do that and some people are not, and that’s me.”

In a separate interview, Ching’s assistant, Ianniello, says she believes he suffered post-traumatic stress disorder (PTSD) brought on by his rescues in Asia.

“With PTSD you keep reliving the moment,” she says. “You relive it because you hope that if you can figure out how it happened you can change it. He has to continue to suffer because they are still suffering.”

Ching at first said he believed only a third of the dogs died, later revising that estimate to less than one half. Some were distributed to local animal-welfare groups to be adopted within China, he says, explaining the disparity between his estimate on survivor numbers and those of his volunteers.

He says the 90 surviving dogs the Animal Hope and Wellness Foundation is caring for in Changsha will be found new homes in the US: “They are coming home – all of them.” Together with the dogs being sent by the Soi Dog Foundation and the Humane Society International, up to 300 of the original 1,000 dogs should make it to new homes overseas.

Some of the criticism levelled at him came from estab­lished groups jealous of the attention he had generated, Ching argues.

“I ask a lot of people on the ground why people don’t like me,” he says. “They tell me, ‘It’s because you are a foreigner coming in and doing things and people have been fighting against this trade for years. All of a sudden everyone is talking about you and it’s not fair.’

“I’m not perfect. I’m not this great person people think I am. I’m just a normal guy trying to do something and I have a lot to learn.”

Ching insists he will return for this year’s festival, in June, but says, “I’m not going to do the same thing. We’re going to start a microchip programme and set up free microchipping for 50,000 to 100,000 dogs. We want to set up checkpoints to scan the dogs and find stolen dogs. People will be scared to go to Yulin because they’ll be arrested.”

In a message to his 47,000 Facebook followers posted on January 10, Ching announced a plan to collect 100,000 handwritten letters from children worldwide to the governor of Guangxi speaking out against the 2017 Yulin festival. “Every year people stand out there to protest,” he writes. “This year let our children be our words. And their voice, the heart we need to save humanity.”

He has no plans to buy more dogs from slaughterhouses – a practice that, even before the rescue in June last year, was opposed in a statement made by 35 animal-welfare groups within China that warned such actions only served to push up prices and profits, thus encouraging the trade.

“By buying dogs in Yulin, you objectively become part of the black market dog-meat trade,” the statement asserted.

The selling of dog meat for human consumption is legal in China, but the transport of dogs across provincial borders for that purpose is not. Therefore, activists say, efforts should be focused on stopping the transport of dogs across China to events such as Yulin. Some overseas groups worked with police and local government officials to step up checks on trucks ahead of last year’s festival.

Nevertheless, “the campaign against the dog-meat trade should be Chinese, not international”, says a senior official from an international animal charity operating in China, speaking on condition of anonymity. “International groups can only take a subordinate role. If the fight against the dog-meat trade is a Western campaign, it will unite dog-meat traders and Chinese people and it will make things even worse. They will say, ‘This is Western cultural imperialism against the Chinese, so let’s unite against it.’”

As the fallout from the Yulin rescue continues, Dalley says the real victims of last summer’s fiasco were the dogs who suffered slow, agonising deaths after being pulled out of the slaughterhouses.

“Those poor dogs just went from one hell to another.”