By Dana Kozlov

CHICAGO (CBS) — A social media posting by a Chicago teenager who’s holding an assault rifle is sparking concerns.

The post prompted the arrest of the gun’s owner, who happens to be the girl’s father and a Chicago firefighter.

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CBS 2’s Dana Kozlov reports the teenage girl posted a controversial photo on Snapchat holding her father’s rifle.

In the 14-year-old girl’s original post, she is standing, holding what Chicago Police say is an assault rifle. Along with her ‘selfie,’ she wrote: “Don’t worry. I won’t shoot up Lane,” meaning Lane Tech High School.

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The post caught the attention of Lane Tech staff and Chicago Police, who investigated and found that the rifle was real and belonged to the girl’s father, Chicago firefighter Michael Matuszewski.

Chicago Police say the 60-year-old first responder is now cited with two violations over the incident for having a firearm accessible to a minor and possession of an assault weapon within city limits, which is not allowed.

Police say Matuszewski was taken into custody Wednesday.

His daughter, reportedly a student in Lane Tech’s Academic Center, will not be charged. Lane Tech administrators also sent an email to parents about the picture Wednesday stating, “CPD deemed there was no threat to the school and at no time was there ever any safety risk to students or staff.”

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A Chicago Fire Department spokesperson says internal affairs is also investigating, adding the Chicago Fire Department holds its firefighters and paramedics to a higher professional standard but must also allow its members due process. He added the peace of mind and safety of students is of great concern.