CHICAGO (CBS) — The Lake County Sheriff’s Department is now investigating allegations that at least seven children from Gages Lake School were physically abused by two staff members.

It happened more than a month ago, but the school district is just now notifying parents.

Staff members were trained in de-escalation techniques as they work with students facing a number of learning difficulties. At Gages Lake School two paraprofessional staff members are no longer in the classroom and handed in their resignations following investigations by the special education district of Lake County and the sheriff’s department.

The school serves students with physical, emotional and other learning obstacles.

May 16 a parent contacted the school about a staff member’s restraint of his child during a “behavioral intervention.”

A review of security cameras found not one but seven children between the ages of seven and nine being handled roughly by the same two staffers, according to the sheriff’s department.

The district said the now former employees “did not comply” with the “deescalation and physical restraint protocols” despite extensive training.

The district claims DCFS and law enforcement were notified immediately, but a letter to parents was not sent until more than a month later.

The father who says his daughter is at the center of this says the school allowed him to view the surveillance video.

“She was having a really rough morning, and they had to take her out of the classroom,” said Robert Outland.

“And so they brought her into this area where they’re supposed to cool down and such, and she was coming at the aide, you know, consistently for 25 minutes. I saw the video. It was a rough watch for multiple reasons, watching my kid come at this man. But then I see the same man just pushing my kid. I mean, it enraged me. I have to admit I had to take a real long breather afterwards.”

The sheriff’s department is conducting interviews with parents and their students.

No charges have been filed.

Charlie De Mar