A silverback gorilla charged at a family and slammed into the glass barrier separating the enclosure from visitors at an American zoo in Omaha, Nebraska, startling visitors who were watching the animals on the other side.
In the video that was uploaded on YouTube, the gorilla that attacked was at first standing at the back of the enclosure, and did not appear to take notice of the family.
However, moments before the attack, a young girl can be seen mimicking the apes by beating her chest in the reflection of the glass, which may have provoked the gorilla, reported Mashable.
"Don't do that," a young boy can be heard telling her.
But it's too late, as the gorilla begins to run towards the glass where the children were standing along with two adults who were filming the animals.
The force of the gorilla slamming itself into the wall was so strong that a large crack appeared in the glass.
The terrified children immediately flee towards the nearest exit, and a man believed to be the father of the kids says "Oh man" and even gives out a chuckle.
The video, titled "When a Silverback attacks", has been viewed over 17 million times since it was posted on YouTube last week.
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