A gorilla at the Cincinnati Zoo was shot and killed Saturday after it grabbed and dragged a 4-year-old boy who fell into the animal’s enclosure, an official said.

Authorities said the boy, who fell 10 to 12 feet into the gorilla exhibit moat, is expected to recover after being picked up from the moat and dragged by the gorilla for about 10 minutes. The boy was taken to Cincinnati Children’s Hospital Medical Center. Zoo officials said he was alert when he was transported there.

Director Thane Maynard said the zoo’s dangerous animal response unit that practices for such incidents decided the boy was in “a life-threatening situation” and they needed to put down the 400-pound-plus 17-year-old male gorilla name Harambe.

"They made a tough choice and they made the right choice because they saved that little boy's life," Maynard said. "It could have been very bad."

He said the gorilla didn’t appear to be attacking the child, but the animal was “extremely strong” in an agitated situation. Maynard added that tranquilizing the gorilla wouldn’t have knocked it out immediately, leaving the boy in worse danger.

According to the Cincinnati Enquirer, fire department officials said the boy was in between the gorilla’s legs when it was shot.

Maynard said it was the first time that the team had killed a zoo animal in such an emergency situation, and he called it "a very sad day" at the zoo. The lowland gorilla is an endangered species. He said that no one in the zoo’s 38 years has anyone gotten into the enclosure.

The incident was reported at around 4 p.m. The area around the gorilla exhibit was closed off Saturday afternoon as zoo visitors reported hearing screaming.

Harambe came to Cincinnati in 2015 from the Gladys Porter Zoo in Brownsville, Texas.

Hospital officials said they couldn't release any information on the child. Authorities hadn't released the child's name.

Cincinnati Police Department spokesman Lt. Steve Saunders said no chargers were being pursued against the child’s parents.

The zoo said Saturday night the Gorilla World area would remain closed until further notice after earlier saying it would be open on Sunday. Maynard said the zoo believed the exhibit remains safe. They are still investigating, but zoo officials believe the boy crawled through a railing barrier, then fell into the moat.

The zoo prides itself for its work in protecting endangered species, and has been part of successful captive breeding efforts in recent years in the effort to save the endangered Sumatran rhino.

The Associated Press contributed to this report.

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