What Happened Inside the Gorilla Enclosure at the Cincinnati Zoo Leading to the Fateful Shot

— -- For the young boy who crawled over a barrier at the Cincinnati Zoo and fell into an enclosure with a 450-pound gorilla, it was a fateful 10 minutes that ended with the gorilla being killed and the boy being rescued without life-threatening injuries. But the debate over Harambe the gorilla's interactions with the boy and why the 17-year-old ape had to be shot continues to polarize opinions after Saturday's incident.

"You see [video] clips, you might not see everything that happened," Thane Maynard, director of Cincinnati Zoo, said Monday. "There are quotes directly from [the] Cincinnati fire department in their official report, this child was being dragged around. His head was banging on concrete. This was not a gentle thing. The child was at risk. We're very fortunate that he's okay."

Here's what happened inside that enclosure during the approximately 10-minute ordeal, based on accounts from the zoo director, a witness, video clips, 911 call logs, police records and fire officials.

3:52 p.m.: Over the Barrier and Into the Moat

At 3:52 p.m. Saturday, someone called police to report that a baby had fallen into a gorilla moat, according to police call records.

Maynard said the child "went over the barrier and then through the bushes and into the moat."

"It's about 15 feet down into a foot-and-a-half of water. So, he must be a tough little kid because that's a lot to do right there. He was splashing around in the water," he said.

3:54 p.m.: Harambe Takes Notice

At 3:54 p.m., the boy's parent reported a gorilla standing over the child in the gorilla moat.

"The little boy, once he fell, I don't think the gorilla even knew that he was in there until he heard him splashing in the water," witness Brittany Nicely told ABC News, explaining that zoogoers' screams drew more attention.

Maynard said, "Naturally, the visitors -- it was a crowded day, we had over 7,000 people in the zoo, they were reacting and Harambe noticed that."

"On seeing him, he [Harambe] went down," Maynard said. "He went into the water with him, swished him around in the water some, mostly by the ankle and then decided he needed to take him up onto the land."

Nicely told ABC News "The gorilla rushed the boy, but did not hit the boy. ... He almost was guarding the boy, was protecting him."

"The gorilla wasn't hitting him, wasn't hurting him. He was curious. He was checking him out," she said.

From 3:56:05 to 3:56:33, callers reported the gorilla dragging the child around the pen; the gorilla holding the child on top of the rocks; and the gorilla swinging the child back and forth on top of the rocks.

Video obtained by ABC News shows the gorilla dragging the small boy through the water in the enclosure.

At 3:56 p.m., a call asked for medical response to a service gate to the zoo.

4:00 p.m.: The Shooting and Rescue

A call came into police at 3:59 p.m. reporting units responding.

When fire department personnel arrived at the enclosure, "they witnessed a gorilla who was violently dragging and throwing the child," the fire department said in its report.

At 4:00 p.m., there was a report to police about trying to tranquilize the gorilla to get to the child, and at 4:01 p.m. was the much-awaited call reporting the child was safe, rescued and being transported.

A Cincinnati Zoo employee shot the gorilla with a rifle when the child was in between his legs, and zoo employees then unlocked the gate and firefighters quickly retrieved the child, the fire department reported. The boy was hospitalized and later released.

"When it was determined that the child was being injured, not potentially injured but was being injured both down in the moat and up on the ground, we had to make a decision to shoot him and we did," Maynard said Monday. "We stand by our decision and we’d make the same call today."

The boy's family said in a statement Sunday that he "is home and doing just fine."

The Cincinnati Police Department is investigating the circumstances that led up to the child falling into the enclosure.