JC Pretorius, who runs the Tau Thaba Lodge in Heilbron in the Free State said a woman who had taken the visitors to see the big cats at his lodge told him that the boy had apparently been standing too close to the fence when it happened.
"She said that she told them to stay away from the wire," said JC Pretorius by telephone.
"The more she said it, the more they wanted to take pictures," he said.
Before they knew it, the tiger was clawing at the boy.
The electric fence had been switched on but he thinks the tiger may have got a fright when he felt the electric pulse and instinctively thought the boy was trying to hurt him.
"Those nails are like knives," said Pretorius.
"It is the first time in my 16 years here that something like this has happened," he said.
"This is for me very bad."
Pretorius does not blame the tiger and has no intention of putting it down after the incident.
Advertisements for the lodge invite visitors to a close encounter with lions and at night they can hear them roaring.
EWN reported that the boy is recovering in hospital but his father believes the lodge was negligent.
“The fence was off that’s why the tiger could touch the fencing and grab the child,” he told EWN.
“The tiger was very strong, he wanted to take the feet through the gate.”
This is that latest in a number of attacks by animals in captivity.