Criminal charges will not be filed against the mother of a three-year-old boy who crawled into the Cincinnati Zoo's gorilla exhibit last month, leading zoo authorities to shoot the endangered animal dead, a prosecutor said Monday. 

Hamilton County Prosecutor Joe Deters said the mother was attending to the three other children with her when her son "just scampered off" on May 28. The boy had crawled through a barrier and fell 12 feet into a moat within the enclosure, when the 17-year-old gorilla grabbed the boy.

Though some have called for child endangerment charges against the mom, Michelle Gregg, Deters said she was not being reckless and didn't put her son at risk intentionally, TIME reports. Deters said Gregg had her back turned when the three-year-old ran off.

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"If anyone doesn’t believe a three-year-old can scamper off very quickly, they’ve never had kids. Because they can. And they do," Deters said during a news conference.

"Had she been in the bathroom smoking crack and letting her kids run around the zoo, that’d be a different story," he said. "She was being attentive to her children, by all witness accounts."

The ruling comes after more than a week of fierce social-media backlash against the zoo and Gregg. 

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Many have claimed that Harambe, the 450-pound western lowland gorilla, wasn't actually being rough with the boy, but rather protecting him.

Still, the zoo has stood by its decision to kill the ape, asserting that the situation was life-threatening.

The zoo plans to reopen its gorilla exhibit, Gorilla World, Tuesday, after making modifications to its public barrier.