Crowds of people scattered from Big League Dreams in Chino Hills on Monday after there were reports of an active shooter in the area. 

A massive contingent of law enforcement officers rushed to the park, located in the 16000 block of Fairfield Ranch Road, at around 7:45 p.m. after receiving reports of a man who was armed with a gun. They evacuated the facility as they began to search for a potential suspect.

"So far, deputies have not located a crime scene, a suspect or any witnesses who actually saw the man with a gun," San Bernardino County deputies told CBS News Los Angeles. 

They are still working to interview as many people as they can as their investigation continues.

According to witnesses who were at the field on Monday night, someone shouted "gun" after some loud noises were heard at the field. This was followed by widespread panic amongst the hundreds in attendance. 

"There was a whole bunch of commotion, people running from everywhere. it was panic, nobody really knew what was going on," said Charlie Herd. "It was pandemonium. It was nuts. It was terrifying, very terrifying for all the kids that are here. this is going to be embedded in their memories for a very long time. It's a very sad and unfortunate event."

Herd said that he and his family were there for a baseball game.

"Not something at all we were expecting coming to a fun, family, baseball event, where it's just supposed to be a good time for everybody," he said. 

According to some witnesses, there was construction happening near the fields and that there was heavy machinery that was in use at the time that the noises were heard.

Big League Dreams is a well-known complex of baseball stadiums, each of which is modeled after a Major League Baseball stadium. Some of the replica fields include Fenway Park, Wrigley Field and Ebbets Field. It was opened in 2003 and has since seen thousands of games and tournaments.