A 17-year-old gorilla named Harambe was shot dead after he grabbed a four-year-old boy, who slipped into the animal's enclosure on May 29, Saturday.
The zoo keepers considered the situation as life threatening, when the lowland gorilla carried the boy around its habitat for 10 minutes, Cincinnati Zoo Director Thane Maynard said during a press briefing. The child had no injuries when he was taken to Cincinnati Children's Hospital.
The boy went under the rail through wires and over the moat wall before he fell into the animal's area, according to Maynard.
"The child was not under attack but all sorts of things could happen," Cincinnati Zoo Director said in a report by CNN.
"He certainly was at risk," he added.
Maynard said they did not use tranquilizers to subdue the gorilla because it could have taken some time for the drug to take effect, so they decided to use a deadly force.
The director added it was not easy for the team to come up with this decision because the boy's life was at risk.
"They made a tough choice and they made the right choice because they saved that little boy's life," Maynard said in a report by Fox.
"It could have been very bad," he added.
According to Cinnati director, although the Harambe was not attacking the kid, the animal was "extremely strong" in an agitated situation. Fire department officials said the boy was in between the legs of the Harambe, Cinnati Enquirer reports.
After the killing of the gorilla news went viral, many got mad. More than 2,000 people signed a petition on Change.org that criticized Cinnati Police department and zoo for killing the animal, and even called the parents of the kids to be "held accountable for their actions of not supervising their child," according to Reuters.