Dangerous big cats seem more like cuddly kittens at controversial zoo where visitors come face to face with lions and tigers Tourists are allowed to pet animals at Argentina's Lujan Zoo Zoo says the creatures are so well-fed they do not consider humans as food However, some animal rights activists believe the animals have been sedated Similing as they come face to face with some of nature's most dangerous predators, these visitors to a controversial zoo can cuddle up to lions and tigers without fearing they might not live to tell the tale. Even the most feared mammals appear no scarier than a domestic cat at Argentina's Lujan Zoo, where animals are raised alongside dogs and are used to human contact. Since it opened in 1994 there has not been a single report of an attack, although many critics of the zoo believe that this record has been achieved through drugging the animals. Too close for comfort? This tourist at the Lujan Zoo in Argentina smiles as she cuddles up to a lion Up close and personal: Since it opened in 1994 there has not been a single report of an attack at the zoo Domesticated: Officials also say that the animals are raised alongside dogs, and learn to mimic the domestic pets' friendliness towards people Although in their natural habitat the big cats such as lions and tigers would be feared, these creatures don't seem to mind the tourists cosying up to them for a photograph, and even young children are allowed to pet them. The zoo claims that the animals are so passive and friendly because they are so well-fed that they would have no cause to ever think of humans as food. Officials also say that the animals are raised alongside dogs, and learn to mimic the domestic pets' friendliness towards people. Passive: Although in their natural habitat tigers would be feared, these creatures don't seem to mind the tourists cosying up to them for a photograph Lethargic? Some animal rights groups say the creatures have been sedated New start: Many of the animals at the zoo are said to be former illegal house pets, offered to the zoo after they have outgrown their homes The zoo has been criticised by some visitors and animal rights groups who say that the creatures seem lethargic - as if they had been drugged, according to Atlas Obscura. However, keepers maintain that if they animals were sedated to the extent suggested the drugs would kill them. As well as bears, tigers and lions the zoo holds two female elephants, a wide variety of reptiles and birds. Many of the animals at the zoo are said to be former illegal house pets, offered to the zoo after they have outgrown their homes. Creature comforts: Two tourists enjoy a close encounter at the zoo