DIXON, Ill. (AP) — The lawyer for a 19-year-old charged with firing shots at an Illinois high school during graduation rehearsal says that his mother legally owned the gun he’s accused of using.

Sauk Valley Media reports that Matthew Milby Jr. appeared in court Wednesday via video from the Lee County Jail. He’s being held on $2 million bail in connection with last week’s shooting at Dixon High School.

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Matt Milby was charged with three counts of aggravated discharge of a firearm following a shooting at Dixon High School on May 15.

Milby was injured in an exchange of gunfire with a school resource officer. No one else was injured.

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Defense attorney Thomas D. Murray said following Wednesday’s hearing that Milby’s mother, Julie Milby, has a valid Firearm Owner’s Identification card in Illinois.

Julie Milby, formerly Julie Mitchell, convicted of felony – resisting an officer in Osceola County, FL in 1991.

Police are still investigating how Matthew Milby obtained the 9 mm rifle, which police have said his mother bought in 2012.

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