On Saturday, a three-year-old boy fell into the gorilla enclosure of Harambe, a male Western lowland silverback gorilla. The boy climbed over the barricades and fell 15 feet into a moat in the enclosure.

In the above video, the gorilla can be seen approaching the boy and, according to the man who recorded it, he appeared to be protecting the young boy. The zoo authorities on the other hand say they had reason to believe that the gorilla appeared excited and agitated and hadn't dispersed from the area like the other gorillas had.

First responders "witnessed a gorilla who was violently dragging and throwing the child," Cincinnati Fire Department Chief Marc Monahan wrote in a statement.

To save the child, the 17-year-old gorilla was killed and after a harrowing 10 minutes, the boy was removed and taken to a local hospital. "We are all devastated that this tragic accident resulted in the death of a critically-endangered gorilla," zoo director Thane Maynard said later in a statement. "This is a huge loss for the Zoo family and the gorilla population worldwide."

However, the endangered nature of the gorilla has sparked outrage online with a petition demanding that the parents be prosecuted for negligence for allowing the incident to take place. It has earned 275,000 signatures.

One question raised is why the authorities didn't use a tranquilliser. The zoo authorities suggested that tranquillisers take time. "That child's life was in danger. People who question that don't understand you can't take a risk with a silverback gorilla – this is a dangerous animal," Maynard said. "Looking back, we'd make the same decision. The child is safe."

Another accusation levelled at the zoo has been the failure of the enclosure to prevent people from entering. Maynard said that this was the first such incident in the 38 years of the zoo's existence. "We live in the real world, we make real decisions. People and kids can climb over barriers. We work hard to make sure this zoo is safe. People can climb over barriers, that's what happened."

Regarding the incident, People for Ethical Treatment of Animals (PETA) has questioned the entire purpose of zoos. "Even under the 'best' circumstances, captivity is never acceptable for gorillas or other primates, and in cases like this, it's even deadly," PETA said in a statement.

Julia Gallucci, a primatologist with PETA, suggested that the gorilla was trying to nurture the child, referring to a incident in 1996, "Consider Binti Jua, the gorilla who carried a child to a zookeeper's gate."

This comes close on the heels of an incident that took place at the Nehru Zoological Park in Hyderabad where a drunken man entered the lion enclosure in an attempt to shake hands with one of the lions. Thankfully, neither human nor animal were harmed.

Last Saturday, a man entered the lion enclosure at a zoo in Santiage, Chile in an attempted suicide and began taunting the animals who started attacking. The zoo authorities were forced to shoot two lions with live ammunition in order to prevent the situation from escalating.