CHICAGO (CBS)– Dolton Police are questioning a security guards’s response to a fight that broke out at an alternative school, Academy for Learning, on Nov. 28.

A security guard who stepped in to break up the fight is being accused of taking things too far.

Police say he could face charges of aggravated assault and unlawful use of a weapon.

“The student was not listening to the security officer, to break it up,” said Dolton Police Chief Robert M. Collins, Jr.

So he took matters into his own hands, placing his hands on the student in an attempt to control him.

It was reported that the security guard slammed one student to the ground and got on top of him, wrapping his hands and fingers around his neck.

“That was the point, where it is reported that, he threatened to kill him,” Collins said.

As the argument escalated, the security guard’s co-workers asked him to step outside to cool off.

He complied, but that’s when the teen and another student stepped outside the front door of the  school.

Collins said the suspect began taunting one of the students. That’s when he pulled out a weapon.

At some point, the weapon was pointed at the chest of one of the students, police said.

The security guard left the school after the incident and police haven’t interviewed him yet.

“What we need to do is make sure we have all our witness and victim statements and involve the state’s attorney ’cause we will have to pick this subject up and interview him, before we start to consider charges,” Collins said.

ECHO Joint Agreement operates the school.

In a statement they say the security officer is not allowed on any of their school properties. They also say they’re cooperating with police and DCFS to make sure the appropriate action is taken against the officer.

The security firm he works for had no comment.