Johannesburg - Keeping wild animals as pets is becoming a growing phenomenon, the Society for the Prevention of Cruelty to Animals (SPCA) said.Pictures of a tiger cub tied to a leash in its owner's backyard were circulated on Facebook, prompting members of the public to urge the SPCA to remove the animal. The animal is being kept as a pet at a Boksburg home.But the SPCA's manager for wildlife protection, Ainsley Hay, said their hands were tied."The issue is, it's not illegal to have an indigenous or exotic animal as a household pet," said Hay, adding that the law needed to be changed."Our concern is the safety of the animal, as well as the safety of others. The animal can become extremely dangerous to the public."Hay said the SPCA had approached the Gauteng Nature Conservation group, which had in turn informed them nothing could be done about the tiger cub.The wildlife protection officer went on to say people thought raising a wild animal was "cool". But, she added, they failed to consider the implications of what would happen once the wild cat matured.Neither the Gauteng Nature Conservation Group nor the tiger cub's owner could be reached for comment.