CHICAGO – A Chicago teen tasked with making sure students arrive and depart a local school safely is facing criminal charges after police allege he shot a 17-year-old girl after school Wednesday.

Prosecutors charged Shelby Crawford, 18, with multiple crimes for shooting a 17-year-old student after a scuffle with a group of students around 4:15 p.m. Wednesday, when authorities allege he was working as a Safe Passage worker on West 111^th Place, the Chicago Tribune reports.

Safe Passage workers are employed by Chicago Public Schools to ensure students can travel safely though rough neighborhoods to school.

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CPS officials told the media Crawford was not part of the Safe Passage program. He was a “student support worker” for students arriving and leaving from Foundations College Prep, according to the news site.

Regardless, Cook County prosecutors and Crawford’s family contend he was hired about two months ago despite his probation status for a previous gun crime.

District spokesman Bill McCaffrey told the Chicago Sun Times Crawford was not working “in a security capacity.”

Police allege Crawford was working for CPS when he got into an altercation with a group of teens. Crawford’s family said the group asked for his gang affiliation and when he denied involvement in gangs, was punched in the eye and robbed of his cell phone and school-issued radio.

“He then followed the group and opened fire, striking a 17-year-old girl in the chest with a bullet that lodged between her rib cage and lung,” the Tribune reports.

The victim was rushed to Advocate Christ Medical Center in Oak Lawn in serious condition, according to the Times.

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About two hours after the incident, police patrolling the area of 69^th Street and Indiana Avenue came across a group of teens at an abandoned house, and allegedly found Crawford in vacant lot behind the house.

Police “saw him throw the gun to the ground and walk away, grabbing the zipper area of his pants, the prosecutor said. Crawford told arresting officers he was just urinating, according to the arrest report. A blue steel .9 mm handgun loaded with five live rounds was found near a mattress in the yard, the report said.”

Judge James Brown was reportedly shocked by the news when he ordered Crawford held on a $900,000 bail Friday, the news site reports.

“A Safe Passage employee?” the judge questioned.

Crawford’s family told the media after Friday’s court proceedings that Crawford was simply defending himself.

“We’re not validating the fact that a gun was discharged and a girl was hit,” Crawford’s aunt, Katie Arsberry told the Tribune. “We’re not in agreement with that … but if you’ve got 10 people attacking you, you’re going to defend yourself.”

Samantha Harris, Crawford’s mother, said her son’s previous gun conviction stems from a traffic stop in which a gun was found in a vehicle with her son and others. Crawford was a student at the alternative school Chicago Excel Academy and was expected to graduate next spring, she said.

The police arrest report confirms Crawford suffered from a swollen lip and facial injuries that he claimed were the result of the scuffle with the group of students.

“Crawford is charged with unlawful use of a weapon, aggravated battery with a firearm and not having a Firearms Owner Identification card, police said,” according to the Times.