Hundreds of Chicago Public Schools employees were banned from the first day of class Tuesday after they failed criminal background checks spawned from news reports of criminals working in schools.

CPS CEO Janice Jackson told the Chicago Tribune 266 employees were flagged for criminal behavior and banned, while another 245 refused to submit fingerprints for the checks. The first group, which includes 60 teachers, is now under review to determine if they are a threat to children, while the second group will be disqualified from employment if they don’t get with the program, she said.

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Jackson said employees were flagged for violence, sexual misconduct, drug activity or other dangerous crimes, which means the city employs potentially hundreds of criminals to work with students in schools.

“CPS will be conducting thorough investigations in all of these instances to better understand the circumstances of each unique case. Employees were only removed based on the results of their background checks if arrests were identified that suggest a potential history of violence, sexual misconduct, or dangerous criminal activity,” Jackson said.

According to the Tribune, “CPS officials began the massive effort to redo background checks for school employees in June following a Tribune investigation that found some CPS employees who abused students had criminal backgrounds.”

The $3 million effort involved collecting fresh fingerprints to run employees through state and federal databases, though district officials won’t discuss how they determine which employees stay and which are let go. Jackson said convictions for sex abuse, some drugs and other crimes result in immediate termination, but would not reveal how many CPS employees have been fired.

“There is no doubt that the overwhelming majority of adults serving in our schools are fully committed to keeping children safe, and the small minority of employees whose records require deep inquiry will receive the thorough review they deserve,” Jackson said.

For about 2,000 CPS employees, that process was still ongoing last week, with just days left before the new school year. CPS officials required employees to resubmit fingerprints by Aug. 3, but several teachers told WMAQ they received emails last week reminding them they can’t come to work until they get an official go-ahead.

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“The results of your background check are still pending, and we will follow up with you as soon as possible once we receive them,” the email read. “Please be aware that you cannot participate in student programming until you are cleared.”

Chicago Teachers Union officials, meanwhile, describe the process as “a hot buttery mess.”

“The bed they made is that they said they were going to do this huge number of checks and it’s a hot buttery mess,” CTU president Jesse Sharkey told WMAQ.

The CPS fingerprint checks involve about 46,000 employees, as well as volunteers, venders and others who have contact with students.

Sharkey thinks training and talking to teachers about criminals in schools should take precedent over actually removing the criminals from the building.

“Instead of doing press releases, fingerprinting, background checks, they should actually be doing training, sitting down and working with people who are on the front lines of the schools to make processes to make sure that no students get hurt again,” he said.