According to the Buena Park Police Department, officers were rushed to the scene after receiving reports of gunfire.
"I saw a whole bunch of people running out and that's what triggered me and I was like, 'What's happening?'" said mother Tina Rodriguez. "I asked more people and they were like, 'Oh, there was a possible shooting.' But I wonder how that could've happened with all the metal detectors."
Officers on the scene determined there wasn't a shooting, but began investigating reports of fights.
Knott's Berry Farm shut down after multiple fights among teens break out, park says
ABC7 viewers have called Eyewitness News and reported seeing guests in a panic.
"I just seen like people fighting and hitting security," said a teen. "I seen people on the floor bleeding. It was like a riot. It was bad."
Video shows guests rushing out after Knott's Berry Farm fights
Authorities shut down the park around 8 p.m. and asked guests to avoid the area.
It's unclear if there were any injuries.
Meanwhile, Knott's Berry Farm issued the following statement:
"The safety of Knott's Berry Farm's guests and associates is always our top priority. On Saturday evening, the decision was made to close the park 3 hours early due to unruly behavior and altercations involving a number of teenagers. This behavior did not align with our park's values, and was not the experience we want any guest to have while visiting Knott's Berry Farm."