Michelle Gregg, the mother of the 4-year-old boy who fell into the gorilla pen at the Cincinnati Zoo on May 28, can be heard frantically pleading for help in newly released 911 calls.

"My son fell in the zoo exhibit at the gorilla, at the Cincinnati Zoo. My son fell in with the gorilla. There is a male gorilla standing over him!" Gregg screams into the phone. The operator then informs Gregg that someone has already made the call and that help is on the way. “He’s dragging my son. I can’t watch this!” Gregg frantically tells her.

“Be calm, be calm!” she can be heard yelling to her son, who at one point was being dragged through the moat by the 400-pound, 17-year-old male gorilla named Harambe.

As previously reported, zoo officials ultimately chose to shoot and kill Harambe to save the boy.

“We are heartbroken about losing Harambe, but a child’s life was in danger and a quick decision had to be made by our Dangerous Animal Response Team,” park director Thane Maynard wrote in a statement, explaining that “tranquilizers do not take effect for several minutes and the child was in imminent danger.”

The Associated Press reported on Tuesday, May 31, that the boy’s parents are now being investigated by the police. According to the AP, authorities will be focusing on the parents' actions leading up to the incident.

Celebrity animal activists, including celebrities Kaley Cuoco, Piers MorganKatharine  McPhee, Ricky Gervais and Alyssa Milano, took to social media to express their fury over the killing of an innocent animal, but the zoo continues to stand by its decision.

"That child's life was in danger," Maynard said during a press conference on Monday. "People who question that don't understand you can't take a risk with a silverback gorilla — this is a dangerous animal. Looking back, we'd make the same decision. The child is safe."

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