Rifle Used In Dixon School Shooting Bought By Teen's Mom: ISP

DIXON, IL — A Dixon teenager accused of shooting at an officer used a gun purchased by his mother, Illinois State Police announced Thursday afternoon. Matthew A. Milby, 19, had a 9mm semi-automatic rifle when he fired several shots near the Dixon High School auditorium, where about 150 students had gathered Wednesday morning to rehearse for graduation, police said.

State police said School Resource Officer Mark Dallas rushed to the scene and confronted Milby, chasing him from the scene. The gunman fired several times at Dallas during the foot chase, police said. The officer fired back and hit Milby before he was taken into custody. There were no other injuries reported.

Milby was transferred from a local hospital to Lee County Jail Thursday and held on a $2 million bond. He has been charged with three counts of aggravated discharge of a firearm – at a school employee, in a school building and toward a peace officer. Police said more charges may still be filed. Investigators are reviewing surveillance footage from inside the school, but there has not been any video footage found from outside the school, according to state police.

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Milby's mother told reporters her son had recently been bullied and beat up. She said she does not know how he obtained the gun, according to the Associated Press, which reported another graduation rehearsal would be held Thursday afternoon and the ceremony remained set to go ahead for Sunday.

"That's a good question," she said, according to WIFR. "We don't have guns. I don't have any guns in the house. I've told them what I think of where it came from." According to Illinois State Police, she purchased it in 2012. Police said the investigation into how the teen acquired the weapon is ongoing.

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At a news conference Wednesday, Dixon Police Chief Steve Howell praised Dallas' response during the incident.

"Because of his heroic actions, countless lives were saved," said the chief. "We are forever indebted to him for his service and his bravery."

A lawyer issued a statement on behalf of Dallas Thursday saying the officer's son had been among the students gathered in the gym he heard gunfire, according to the Chicago Tribune.

“Mark is humbled by the tremendous outpouring of support for his actions at Dixon High School. He genuinely appreciates those who have referred to him as a hero,” the statement said.

Top photo: Dixon Police Department School Resource Officer Mark Dallas (Dixon PD) / Matthew A. Milby booking photograph (Illinois State Police)