³ÉÈËÂÛ̳

A three-year-old boy who fell into a gorilla enclosure at Cincinnati Zoo, leading to the animal being shot, is said to be "doing well".

Harambe, a 17-year-old endangered western lowland gorilla, was shot dead after he started dragging the boy.

Police said they were investigating the actions of the boy's parents leading up to his fall.

On Wednesday, they also released a recording of the call the boy's mother made to police.

In it, she is heard crying: "He's dragging my son...I can't watch this." She repeatedly shouts "be calm" at the boy.

In a statement on Wednesday, the boy's family thanked zoo staff "for their actions taken to protect our child".

They also asked that any donations be made to the zoo in Harambe's name. The zoo has suggested donations would go towards a gorilla conservation project in the Congo.

The online reaction to Harambe's death

The zoo says it had no choice but to kill the gorilla, and has defended its safety measures around the enclosure.

But animal activists have accused the zoo of negligence.

Stop Animal Exploitation Now, a Cincinnati-based animal rights group, said it had filed a federal complaint against the zoo with the US Department of Agriculture (USDA).

The parents of the boy, who suffered minor injuries in the incident, have also faced heavy criticism on social media.

Video footage showed the boy being dragged through shallow water by the animal in Saturday's incident. Zookeepers shot Harambe soon afterwards.

The zoo maintains it had no choice but to shoot the gorilla as tranquilisers would not have worked in time to save the boy.

It also said its Gorilla World exhibit was safe and exceeded required protocols.

But Michael Budkie, of Stop Animal Exploitation Now, said the USDA should fine the zoo for having an exhibit that the public could access.

"What happened this weekend made it very clear that the physical barriers at the Cincinnati Zoo are not adequate to keep people out of the enclosures, obviously," he said, adding that the enclosure was reported to be over 30 years old.

He also said the zoo had been criticised back in March after two polar bears were able to wander out of their pen into a service hallway.