Outrage on social media continues four days after Harambe, an endangered lowland gorilla, was shot dead in Cincinnati Zoo in order to save a child that had fallen into the moat surrounding the animal's enclosure. But a new FB post and the zoo authorities have attempted to explain why they had to take extreme action to save the child.

A new post thats's going viral is by former zookeeper Amanda O'Donoughue, in which she defends Cincinnati Zoo's controversial decision to shoot the gorilla to save the child.

She echoed the statements given by Zoo director Thane Maynard, who had said that shooting the silverback gorilla was the only way to save the child, and that tranquilizer darts may not have worked fast enough.

"I keep hearing that the Gorilla was trying to protect the boy. I do not find this to be true. Harambe reaches for the boys hands and arms, but only to position the child better for his own displaying purposes," she said, while highlighting the dangers of working with gorillas.

"Harambe was most likely not going to separate himself from that child without seriously hurting him first (again due to mere size and strength, not malicious intent) Why didn't they use treats? well, they attempted to call them off exhibit (which animals hate), the females in the group came in, but Harambe did not. What better treat for a captive animal than a real live kid!" she wrote.

She also explained why using a tranquilizer may not have been a good idea.

"They didn't use Tranquilizers for a few reasons, A. Harambe would've taken too long to become immobilized, and could have really injured the child in the process as the drugs used may not work quickly enough depending on the stress of the situation and the dose B. Harambe would've have drowned in the moat if immobilized in the water, and possibly fallen on the boy trapping him and drowning him as well," she wrote.

Read her full explanation here:

Animal rights groups such as 'STOP Animal Exploitation Now' have called for federal fines against Cincinnati Zoo for the killing of an endangered animal due to own negligence at maintaining the enclosure.

An investigation has been launched to confirm the circumstances of Harambe's death.

An online petition demanding 'Justice For Harambe' has garnered thousands of supporters so far.