An Argentine zoo where tourists can pose with lions could be closed over safety laws.
Visitors to Lujan Zoo in Buenos Aires pay £25 for the experience but animal activists have urged the government to investigate.
The Ministry of Agrarian Affairs is concerned that lives are at risk.
The zoo has denied the claims and says the animals, who some say appear to be "drugged," are more like "domestic dogs".
Undersecretary of the Ministry of Agrarian Affairs of Buenos Aires, Leonardo Mascitelli, said: "What is happening here is against the Argentine laws that regulates activities in parks and estates where they are exhibiting animals.
He said the contact was against Article 8 of a local law which bans direct animal contact with the public in parks and estates where animals are exhibited.
It comes after his inspectors were tipped off by animal activists who sent in social media photos of tourists queuing to get in the cages with the zoo's lions, tigers and bears.
An online petition, with more than 11,000 signatures, has been set up to close the zoo.
Some of the complaints included the animals looked like they are "drugged", "neglected" and "not really clean".
The zoo has over 400 animals and is said to offer a "unique interacting experience" in which visitors can pet, stroke, cuddle and even sit on lions, tigers and brown bears.
It insists the animals are raised with domestic pets such as dogs and a keeper is always on hand in case anything goes wrong.
Zoo spokesman Neyen Rivero Longoria told Central News Agency: "The animals are no more dangerous than domestic dogs because we have taught them the boundaries.
"We are the only zoo in the world that practices special training techniques in gentleness."
Longoria added the animals are fed prior to interacting with visitors "so they won't feel hungry when a human is inside their cage".
However the zoo's claims of special training techniques were rubbished by some visitors on TripAdvisor.
The most recent posting on 13 December said: "I do not understand how this can be legal. No wild animal would tolerate the presence of various humans in such a stressful environment, they must be doped with the most disgusting substances."
Another, from Kansas, wrote: "The animals are clearly drugged, especially the lions.
"However, they are taken care of and it was still terrifying to get to get in the cages with them to pet or feed them."
Not everyone is against the zoo. One visitor wrote she was "thrilled" by the experience.
Out of 1,800 reviews only 130 said it was "poor" or "terrible" with more than half (960) saying their experience was "excellent".