JACKSONVILLE, Fla. - A Ribault High School teacher is being hailed a hero after his quick thinking prevented a possible tragedy.

On Wednesday, a fight broke out between students. During the fight, a trespasser, identified as Sharon Kelly, 43, was engaging in the fight and was found with a gun, according to reports.

Lin Shell is the physical education teacher at the high school. He said he didn't recognize Kelly when he noticed her on campus.

“She got out of the car, she was irate, basically saying she wasn’t going to let anyone jump on her family,” Shell said.

The year before, Shell was the Dean of Boys, which allowed him to recognize and create relationships with several parents of the students, except Kelly.

Shell said he remembers four boys getting out of Kelly’s car and entered Ribault. When he did, he followed them.

Shell quickly saw a large gathering of students in the gym and attempted to separate them. Not long after his efforts, chaos ensued behind him with a scurry of flying fists. While this was happening, one of the students told him that he noticed Kelly grab something out of her car and into the gym.

“I came behind the lady and noticed that she kind of had a bag over her hand,” Shell said.

Shell had a double-take. He said he noticed that it wasn't just a bag Kelly was holding.

“Looked again and saw the rear sights of a pistol,” Shell said.

Shortly after seeing Kelly with the weapon, he reacted.

“I came from behind her, I saw that she had a gun, I grabbed her hand, put her hand down and near her elbow and walked her back out, kept her hand down and pushed her back out the door, just basically told her please don’t shoot our kids," he said.

Shell then yelled to a nearby armed school officer who ordered Kelly to drop the gun. When she did, he handcuffed her.

READ MORE: Woman arrested after she was found with a gun at Ribault HS during fight

“The parent could’ve just as easily gone to the front office, spoke to the right people, have things handled the right way," he said.

Shell said he has a message: “At the end of the day, the adults need to be adults and we need to figure this thing out, because if this if this is where we’re at in society raising our kids, we have a real problem,” Shell said.

Shell said this is a message he hopes students also remember instead of turning to fists and violence.