A Missouri mother is suing a day care after she says teachers encouraged her son to fight other preschoolers.

ABC News reported that, according to a lawsuit filed in December 2016, Nicole Merseal's son, who was 4 at the time, was encouraged by teachers Mickala Guliford and Tena Dailey to fight other students at Adventure Learning Center in St. Louis, Missouri.

"My son was very afraid," Merseal told ABC News. "He didn't understand why his best friends beat him up. These are children that he's been around for a couple years. He described them as his best friends. He just doesn't understand why they punched him in the face. ... I don't know any parent that could watch their children go through this and not be upset."

Merseal said her two older sons saw their little brother in the fight.

KTVI reported that, at the time, 10-year-old was in a nearby room with older kids recorded the fight on an iPad. Merseal's attorney, Jennifer Hansen, told ABC news the 10-year-old was one of Merseal's older sons, and he recorded the fight when the teachers didn't intervene.

>> Read more trending news

Video shows children falling to the ground as teachers cheered on the fights. The children have large green gloves, called Hulk Hands, as they hit each other.

Merseal said she contacted police, who interviewed school staff and her children.

According to documents from the Missouri Department of Health and Senior Services, the center’s director, Jennifer Scott, said that Guliford told her the children were bored and “we ran out of things to do.”

The documents say Scott said she called the Child Abuse and Neglect Hotline and filed an incident report after sending Dailey and Guilford home. Dailey and Guilford were fired.

An unidentified child said the fights “happened a lot of times,” according to the report.

“I meant for the fighting with the Hulk Hands to be a stress release exercise,” Guilford said, according to state documents.

“It did not last more than three or four minutes,” she said. “No children got hurt but it was still a bad judgment call on my part.”

The St. Louis Circuit Attorney's Office declined to prosecute the teachers, saying in a statement to KTVI, "There was insufficient evidence to prove beyond a reasonable doubt that any laws were violated. However, that does not diminish the incredibly poor judgment by these adults who had the responsibility to safely supervise these children."

“Upon learning of the incident, the facility director fired the two staff, reported the incident to the proper authorities, and wrote an incident report to document the information,” the St. Louis Department of Health and Senior Services said in a statement to ABC News. “The facility also informed parents about the incident and the actions taken.

“The Section for Child Care Regulation’s report concluded that licensing rules were violated and requested that the facility take additional steps to ensure staff were trained and knowledgeable about age-appropriate activities for children. The facility completed the corrective measures in April 2017.”

Merseal is not satisfied with the actions taken. She is suing for $25,000 in damages.

“The day care should be held accountable," Merseal said. “They gave them a slap on the wrist.”