A teacher at a private Christian school in New York has been placed on leave after holding a mock slave auction in her classroom during a history lesson on slavery.

Rebecca Antinozzi of Chapel School in Bronxville, New York, faced backlash after the parent of one of the students told the media that the teacher let white students bid on and “buy” black students who were made to act like slaves in an auction. The woman, Vernex Harding, said her son was one of the students who was “sold.”

According to Harding’s son, Antinozzi took him and two female students to the hallway and “started to put imaginary chains on our necks, our wrists and shackles on our ankles.”

The students were then taken back to the classroom where white students were asked to bid on them as Antinozzi acted as an auctioneer. When the children were inside the classroom, the teacher started a bidding process and told a student, “You’re a wealthy white man” and started the bidding at $300, Harding said. The incident took place earlier last week and both Harding and her son have said they don’t want to see the private school teacher again. “He was humiliated. My son doesn’t want to see her again, and I don’t want to see her again,” the New York Post reported Harding saying.

State Attorney General Letitia James is investigating the incident. “The reports of racist ‘lessons’ by a teacher at the Chapel School are deeply troubling. My office is monitoring this matter closely,” she said in a statement.

The principal of the school also apologized for the incident and said they have a third party conducting an independent review. “The reported racial insensitivity is unacceptable and we do not condone any action that demeans anyone,” Principal Michael Schultz said. He also said that the faculty will be given sensitivity training and the students affected by the incident will receive mental health support from professionals. “Teachers will address the children impacted along with the additional support of mental health professionals. The emotional state and well-being of our students and commitment to the respect of all people are out greatest concerns,” he further said.

Several parents contacted Attorney General James’ office and said that they went home feeling extremely uncomfortable from the incident. Several of them said while there have been previous incidents with teachers and black students that bordered on being racist, this one was “egregious.”

Antinozzi’s lawyer Jordan Brooks issued a statement to the media, saying the portrayal of the history lesson was reported inaccurately and out of context, it contained false facts and ignored the support the teacher got from a number of parents including African-American parents whose children were taught by her. “Ms. Antinozzi loves her students and is beloved by them. To the extent, anyone took offense to a small portion of the overall lesson that day, that was used solely to emphasize the tragic injustice of slavery, it certainly was never intended. She looks forward to teaching with the same dedication, sensitivity, and passion that she has always shown,” the statement said.

The teacher has been placed on indefinite leave as the investigation continues.

A New York teacher is under investigation for conducting a mock slave auction where she "sold" black students to their white classmates to teach them about slavery in history. In this representative image of a classroom, Sarah Michelle Gellar and Vera Bradley PR and Marketing Director Greg Jaegar speaks to students at Vera Bradley x Blessings in a Backpack Middle School Charity Event at Vista Charter Public School in Los Angeles Sept. 5, 2018. Rachel Murray/Getty Images for Vera Bradley