CHICAGO (CBS) — Students run in fear when a teenager opens fire at an Illinois high school.

CBS 2’s Chelsea Irving has the story.

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The suspected gunman, 19-year-old Matt Milby, is a former student at Dixon High School.

His mother said Matthew was bullied.

“I think what was hurtful and what this all led to was more ostracization,” said Julie Milby. “Matthew told us he got beat up down here, they broke his jaw. Nobody was arrested for it.”

The shooting happened in Dixon about 100 miles west of Chicago.

High school seniors said they knew it wasn’t a joke when the principal started yelling.

“Dr. Grady, our principal, ran out and said ‘get out of here, go’ and then we heard there was a live shooter,” said Dusti Batsch. “It was pretty scary.”

Students describe a chaotic and panicked scene as they ran for safety.

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“I looked at my best friend and she got bumped over and fell off the bleachers. Her eyes glazed over had I grabbed her hand…and we were running,” said student Emma Krull.

Dixon High School police officer Mark Dallas spotted the suspect, a former student, with a gun. When confronted, the suspect ran and fired his gun at officer Dallas. Dallas returned fire, striking the suspect, then apprehending him.

Students were evacuated and started calling their parents.

“That’s a phone call never thought I’d get. I though ‘no,no, no, not today,'” said Christi Batsch.

School officials, students, parents and police applaud the officer’s quick action.

“When shots rang out in the hallway in the school, he charged towards the suspect and confronted him head-on.  Because of his heroic actions, countless lives saved,” said Dixon Police Chief Steve Howell.

No charges have been filed but the suspect, Matt Milby, is doing well in the hospital.

There will be no school on Thursday.

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Graduation ceremonies set for Sunday will go on as scheduled.