A gorilla at the San Diego Zoo terrified visitors by charging at the protective glass surrounding its enclosure so hard that it caused the glass to crack. The incident occurred on Saturday when a 10-year-old western lowland gorilla named Denny launched himself at the tempered glass while playing with another gorilla, breaking through one of the three layers that separate the animals from visitors. “We were looking down at our cell phones and didn’t notice that he had taken a running start, jumped and launched into the glass. He hit it with his elbow or forearm, like right in the glass directly in front of my face,” said Katya Sutil, who was visiting the zoo for her birthday. “When it hit in front me, I was so jolted I fell back a few feet. When I looked up to see what had happened, I saw the gorilla staring directly at me, making eye contact with me, and then a giant crack… 6 feet. It was pretty big.” The zoo confirmed that neither of the gorillas were hurt during the incident. “Denny was not injured,” they wrote in a statement. “Both gorillas will be cared for behind the scenes until the panel has been replaced.”