The fight is on to stop an annual Chinese event which is expected to involve the slaughter of more than 10,000 dogs, some of whom are burned or boiled alive.

The Yulin Dog Meat Festival, in Guangxi province, is a celebration of the June solstice in which thousands of dogs are traded, killed and then eaten in the home or on the street.

Dogs and cats - some with pet collars still around their necks - are swiped from around the country and transported to Yulin in the lead up to the festival. Close to 500,000 pounds of dog meat is consumed.

Last year, protesters flocked to the province in an attempt to stop delivery trucks and buy live dogs back from some attendees. They also prayed for the dogs that were slated to be slaughtered, and photographed some of the proceedings.

And where there is an animal rights campaign, celebrity activists can never be far away. Actors including Ricky Gervais and Ian Somerhalder have joined the effort, sharing graphic pictures of dogs being tortured and encouraging followers to sign Change.org petitions calling on the "barbaric" festival to be stopped. Singers Leona Lewis and Richard Marx were also among those tweeting about the issue.

They steal people's pets to torture & eat. What would you do to someone who you caught torturing your dog? I hope you'd stop them somehow.— Ricky Gervais (@rickygervais) June 15, 2015

I'm ashamed to be a human. Go & look at the images of what they do here. We can't let this happen #StopYuLin2015 pic.twitter.com/805lFm5BDr— Leona Lewis (@leonalewis) June 15, 2015

According to reports, the local government has "banned" the festival - but this has been described as "semantics" by activists. It is not illegal to slaughter dogs or cats in China and thus the event is expected to continue unofficially.

The Humane Society International calls Yulin a "festival of cruelty" and says most Chinese citizens would abhor what takes place there. Its China expert Peter Li went undercover at Yulin in May and witnessed preparations for the festival in full swing.

He described one slaughterhouse as "full of blood, internal organs of the dogs and cats, blow torched carcasses, and freshly slaughtered dogs hanging on hooks". Photographs showed dogs and cats packed into cages without room to move, with some reportedly dying of dehydration or starvation and carcasses strewn around the city's streets.

"Mass dog slaughter is still going on at Yulin despite the local authorities trying to give the impression that's it's ended," Mr Li told the British MailOnline.

"The Yulin government has declared the 'festival' will not happen, but this is mere semantics and thousands of dogs will still die for their meat whether it's called a festival or not."

SAVED! this sweet dog in a Yulin slaughterhouse, named him Ricky to honor our friend @rickygervais #StopYulin2015 pic.twitter.com/kXhABgHw6x— Humane Society Int'l (@HSIGlobal) June 15, 2015

Andrea Dung, from the Duo Duo project, told the UK Independent that during her visit to Yulin in 2014, she witnessed dogs being slaughtered while "still wagging their tails".

Several petitions have been established calling on Chinese governments to do more to halt the hellish events in Yulin, receiving in excess of 850,000 online signatures. One petition, by the California-based Duo Duo Animal Welfare Project, pointed to the dangers posed by rabies infections in Yulin. There had been 338 reported cases between 2002 and 2006, making Yulin one of China's most affected cities, according to the petition.

The festival was also dangerous for humans due to food safety and public health concerns, the organisation said.

In a letter, Gervais said the footage of Yulin captured by HSI had broken his heart. "I will never forget the look of bewilderment and fear on the faces of these poor animals—dogs and cats awaiting a horrible fate," he wrote.

And on Twitter, activists used the hasthag #StopYuLin2015 to amass support for the campaign against the festival.

Both HSI and Duo Duo have representatives in and around Yulin ahead of the festival, dissuading locals from participating and trying to save animals. Their presence last year - and the government's disendorsement - led to a more "subdued" event with fewer deaths than in previous years, according to HSI.

Despite those successes, festivities in Yulin are expected to begin on June 21.

Warning: graphic images below

Sincere apologies. I didn't want to have to tweet these photos. Burnt & boiled alive for flavour. #StopYuLin2015 pic.twitter.com/NF3RKvGQ1X— Ricky Gervais (@rickygervais) June 15, 2015

I know some of the animal stuff I tweet about is genuinely horrific & depressing but that's no reason to not tweet it. We SHOULD get angry.— Ricky Gervais (@rickygervais) June 14, 2015

If you're angered or upset by pictures of animal abuse, don't demand the pictures stop, demand the abuse stops. Every little helps.— Ricky Gervais (@rickygervais) June 14, 2015