A Denver mother is facing charges after she allegedly attacked a school bus employee who would not let her child off the school bus on Wednesday.

A video of the incident from CBS Denver shows parents gathering around the back of the bus while the employee and the mother engage in a brawl. Middle school children could be heard screaming in the background.

Police arrested the parent, Brandi Martin, for third-degree assault of an at-risk adult because the person she allegedly hit was over 70 years old, KDVR reported.

But Martin and other parents who were there say she acted out of self-defense. The Denver Police Department’s probable cause statement says the driver told police he pulled over the bus and did not let anyone off because the kids were acting “unruly.”

Parents in the area say the driver would not let any kids off the bus.

It was “pretty terrifying seeing my daughter being held against her will and not being able to get to her,” Martin said of the incident.

“What hurts me the most are the screams. I can hear them in my dreams,” she told the Denver Channel.

Denver Public Schools was alerted to the incident late on Wednesday and launched an investigation into the incident on Thursday. The school said one of the two employees suffered a broken nose and was taken to a hospital.

Both the driver and the paraprofessional aboard the bus were placed on administrative leave as of Monday.

The school district said the school bus employees should have handled the situation differently.

“It’s clear that was not handled to the expectations we have. It is important as a district that when kids are in our care that they feel safe and cared for and unfortunately that did not happen in this situation,” said Mark Ferrandino, the deputy superintendent of operations.