It’s the first time near the Chicago area since the deadly Parkland High School shootings in Florida that the concept of an armed officer in a high school succeeded in stopping what could have been another mass tragedy.
It was just after 8 a.m. when students at Dixon High School were seconds from the aim of an active shooter. State police identified the accused gunman as 19-year-old Matthew Milby.
“I’m still shocked now, even a few hours after the event my hands were still shaking,” said senior Benny Roach.
Roach was in the gym with 150 classmates practicing for graduation.
“Shots fired at Dixon High School," crackled over police radios.
Roach said he heard four or five loud bangs
“(A) teacher peaks out of a doorway and he comes in and I seen his face he says everybody get out of here go, go,” said student Brandon Stehl.
Sky 5 captured students outside, suddenly forced to perform a real life version of a drill they had practiced for years.
“We heard what sounded like the resource officer yell, like, 'hey, stop,'" Roachsaid.
That would have been school resource officer Mark Dallas, a veteran Dixon cop, who’s own child was also in the gymnasium.
“Oh, his father's a hero, yeah no, so much more worse stuff would have happened today," Roach said of his classmate's dad.
Dallas was shot at but never hit and returned fire as he chased the teenage alleged shooter, striking him once in the shoulder then arresting him, police said.
“He took it head on and went right after him," Roach said. "He did his job"
Milby's mother, Julie Milby, of Dixon, said her son was bullied.
School officials would not address that. They did confirm Milby was at school Wednesday morning because he too was a member of the senior class.
"I wouldn't have dreamed he would do this in a million years," she said.
Julie Milby said she saw Dallas among crowd of parents gathered outside the school waiting to pick up their children. He didnt' say anything to her at the time and she was not yet informed that her son was the accused shooter, she said.
She said she owned the gun her son used - a 9mm pistol - but she didn't keep it at the house. Julie Milby said the weapon was stored at her 91-year-old grandfather's house, and she didn't know her son had it until after the shooting.
She said before the morning's chaotic events her family was excited for Matthew to graduate Sunday.
Milby is charged with three counts of aggravated discharge of a firearm, is being held on $2 million bond and is currently on 24 hour watch in the hospital.
The motive is still unknown.