A nanny in Illinois hit a 7-month-old boy while putting him down in a crib — an assault the child’s horrified mom witnessed on a video baby-monitoring system as she was pumping breast milk at work and yelled at the nanny to stop, prosecutors said.

Mussarat P. Khan, 60, of Skokie, was charged with aggravated battery after the infant’s mother told police she saw the shocking Aug. 26 assault unfold right before her eyes on the system she used to help her feel closer to her son while away from home, Cook County prosecutors said Sunday, according to the Chicago Tribune.

Khan, who had been working for the family for just over two months, grabbed the boy’s arm and leg, whipped him around and hit him so hard that he cried, prosecutors said Sunday.

The mother ordered Khan to stop using the system’s voice communication feature, prosecutors said during a bond hearing.

The nanny, who was arrested Friday, also slapped the baby across the face a few days earlier, prosecutors said. She has no prior convictions for violent offenses, court records show.

A court-appointed attorney for the woman, meanwhile, said she had worked as a child caregiver for more than eight years and has lived in Skokie for more than a decade, the Tribune reports.

The charges against Khan prompted gasps in the courtroom, according to the newspaper. A judge set the woman’s bail at $2,000 and ordered that she not contact the child’s family or any juvenile with the exception of relatives.

“The only reason she stopped was because the child’s mother had video and told her to stop,” Judge Arthur Wesley Willis said.