Harambe, a western lowland gorilla, lived at the Cincinnati Zoo. He was curious and intelligent, and one of two males, along with nine females in the zoo's Gorilla World. The 450-pound ape celebrated his 18th birthday Friday. 

He was killed by zoo officials Saturday.

In the days since, activists are decrying Harambe's death as abuse against a critically endangered species. Thousands have thrown their support behind Harambe's Law, a proposed piece of legislation that would hold zoo visitors responsible for the well-being of endangered zoo animals.

More than 100,000 people from around the world have signed the Change.org petition, addressed to Ohio State Representative Denise Driehaus and State Senator Cecil Thomas.

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"We would like to pass Harambe's Law, so there are legal consequences when an endangered animal is harmed or killed due to the negligence of visitors," the petition reads. "If this law is enacted, it will not only protect the animals, but will hold individuals accountable for actions resulting in harm or death of an animal."

On Saturday, a three-year-old boy slipped into the gorilla enclosure, where Harambe grabbed him and dragged him through a moat.

CNN reported that the boy had gotten into the enclosure by going under a rail, through wires and over a moat wall. A witness said she heard the boy tell his mother he wanted to go into the moat. His mother, distracted by other children, didn't notice her son slip past her.

Another Change.org petition, Justice for Harambe, blames the boy's parents.

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"We the undersigned want the parents to be held accountable for the lack of supervision and negligence that caused Harambe to lose his life," the petition reads.

The petition, addressed to Zoo Director Thane Maynard and the Hamilton County Child Protective Services, which oversees Cincinnati, seeks legal action and urges an investigation into the boy's family life.

"We believe that this negligence may be reflective of the child's home situation," it says. "We the undersigned actively encourage an investigation of the child's home environment in the interests of protecting the child and his siblings from further incidents of parental negligence that may result in serious bodily harm or even death."

Though no official sources have identified the boy or his parents, an unconfirmed report from the Daily Mail identifies the parents as Deonne Dickerson and Michelle Gregg, who have three other children.

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The boy's encounter with Harambe has been disputed. Some say the gorilla wasn't aggressive, but rather protecting the boy from the screaming crowd. Others disagree.

Witness Bruce Davis told WCPO Cincinnati that "it was basically the child or the gorilla."

The Cincinnati Enquirer reports that first responders from the fire department saw the gorilla "violently dragging and throwing the child,"

In a statement on its website, the Cincinnati Zoo described the situation as "life-threatening." 

"The Zoo security team’s quick response saved the child’s life," said Maynard in the statement. "We are all devastated that this tragic accident resulted in the death of a critically-endangered gorilla. This is a huge loss for the Zoo family and the gorilla population worldwide."