• Boy's parents say he is 'doing well'
• Police have released mother's harrowing call to 911
• Harambe the gorilla reportedly lost his mum, brother in gas accident in 2002
• Old footage of Harambe as a baby has surfaced
• Police have launched an investigation into the zoo tragedy
THE parents of a three-year-old boy who fell into a gorilla enclosure at the Cincinnati Zoo, leading to the endangered animal's death, said he is "doing well".
Mother Michelle Gregg, who was with Isiah when he crawled into the pit, and father Deonne Dickerson also thanked zoo staff for protecting their son.
"If anyone wishes to make a gift, we recommend a donation to the Cincinnati Zoo in Harambe's name," they said in a statement, adding they have been offered money but won't accept financial gifts.
"Our child has had a check-up by his doctor and is still doing well. We continue to praise God for His grace and mercy, and to be thankful to the Cincinnati Zoo for their actions taken to protect our child."
The gorilla, a 17-year-old silverback named Harambe, was shot by zoo workers after Isiah fell into its enclosure on Saturday. Police are investigating to determine if charges should be filed against Isiah's parents.
Mother's dramatic 911 call after son's tumble
Police have released mother Ms Gregg's harrowing call to 911 after her son tumbled into the gorilla's pit.
On the recording, Ms Gregg could be heard frantically shouting: "My son fell in the zoo exhibit at the gorilla - at the Cincinnati zoo. My son fell in with gorilla. There is a male gorilla standing over him. I need someone to contact the zoo please."
She was also heard calling out to her son in the gorilla enclosure, "Be calm, be calm!"
"He's dragging my son. I can't watch this," the mother said during the call.
A bystander could also be heard shouting: "There's a baby in the zoo at gorilla moat. Hurry, hurry, the gorillas are out. Oh, my god."
Harambe's tragic past
Harambe reportedly lost his mother and brother in a gas accident at a zoo 14 years ago.
The Mirror claims to have unearthed a Brownsville Herald article which reported Harambe was just a baby when Kayla, who was 10, and her one-year-old son, Makoko, died in a gas leak at Gladys Porter Zoo in Brownsville, Texas in 2002.
Another female, two-year-old Uzuri, also died and several others were injured.
Deputy zoo director and zoologist Patrick Burchfield told the paper at the time another young male was in a "serious condition". It's not clear if that was Harambe.
A video of Harambe taken about a year before the accident has been shared on social media. It shows Harambe, aged about one, affectionately hugging the keeper as she shows him off to schoolchildren.
"Here is a video clip of Harambe when we went to the Gladys Porter Zoo on a classroom field trip. To this day all of my students have fond memories of Harambe," Dan Van Coppenolle wrote on Facebook.
Harambe, a 200kg western lowland gorilla, was shot dead on Saturday by workers at the Cincinnati Zoo who feared he would kill Isiah after he tumbled into the enclosure.
Witnesses said Isiah had wanted to get into the exhibit and climbed over a one-metre barrier, falling 4.6 metres into a moat. Zookeepers shot the gorilla after he violently dragged and tossed the child, officials said.
The boy's mother said on Facebook that he suffered a concussion and scrapes but is otherwise fine. The family has also received death threats.
Animal lovers continue to express outrage over Harambe's killing, with online petitions at change.org drawing thousands of signatures demanding Justice for Harambe.
The death of the gorilla also prompted the animal rights group Stop Animal Exploitation Now to file a negligence complaint on Tuesday against the zoo with the US Department of Agriculture. The group is seeking the maximum penalty of $US10,000 ($13,833).