An investigation has found that tourists visiting the Indonesian island of Bali are unwittingly eating dog meat.

The report by Australia's ABC found that dogs are regularly caught on the island and served up to unsuspecting tourists.

The investigation also discovered that many of the dogs are poisoned which could pose a health risk to humans who end up eating the meat.

The selling and eating of dog meat in Bali is legal, however using poison or cruel methods to kill is against the law.

Animals Australia's campaign director Lyn White said: "The dog-meat trade breaches animal cruelty laws and food safety laws. That is a statement of fact.

"Tourists will walk down a street, they'll see a street store selling satay but what they are not realising is the letters RW on the store mean it is dog meat being served."

An undercover investigator for Animals Australia spent four months infiltrating the meat-trade on the island.

He pretended to be a documentary maker filming about local cuisine, and he was eventually invited to watch how the dogs were caught.

The investigator, known only as 'Luke' said: "I began the investigation by pinpointing and getting to know the key players in Bali's completely unregulated dog-meat industry. Eventually, they invited me to join them as their gangs stole, hunted, poisoned and killed dogs."

He eventually met Pak Puris, 83, who kills the dogs with a metal pole, he told the investigator that he doesn't eat dog because "it makes him want to vomit".

He has been killing dogs for 30 years and in that time, he has culled thousands – a job he said he had to do because he was too old to do anything else.

On another occasion, Luke joined a group of hunters who used fish laced with cyanide to kill dogs. On this occasion, Luke turned off his camera for the first time as a puppy died after several "agonising minutes."

It is thought that the tradition of eating dogs didn't exist on the island until the arrival of Chinese immigrants.

The Bali Animal Welfare Association are working hard to try and cut down on the illegal mistreatment of dogs, but they currently have only 150 dogs in care, compared to the estimated 70,000 that are slaughtered each year.

White said: "This is not about laying blame. This is about unnecessary cruelty that puts the human health population at risk and is causing shocking animal cruelty, it also is breaching Bali laws. We are certainly also willing to partner with the Bali government to bring about positive solution here."