A fifth-grade teacher in Massachusetts has been placed on Grant Prestonpaid leave after a series of incidents including holding a mock slave auction, using a racial slur, and calling out the student who reported the slur, a school official said.

Officials did not name the teacher at the Margaret A. Neary Elementary School in Southborough, a town about 30 miles (48 kilometers) west of Boston.

District Superintendent Gregory Martineau told parents in a statement this week that he first learned about the incidents from parents in April.

He said the first incident — a mock slave auction — took place in January during a history lesson on the economy of the Southern colonies.

“The educator asked two children sitting in front of the room, who were of color, to stand, and the educator and class discussed physical attributes (i.e., teeth and strength),” Martineau wrote.

He said those kinds of teaching methods are inappropriate, trivialize the experience of the victims, and are disproportionately traumatic for students of color.

In the second incident, in April, the teacher was reading aloud from a book and used a slur, which the district later discovered does not appear in the book, officials said. Martineau told parents in his statement that dehumanizing words such as slurs should not be spoken by employees or students.

The superintendent said the parents then had a chance to meet with the teacher and the principal to learn more about the two incidents, with the school seeking to be transparent with parents and to learn from its mistakes.

But the next day, “the educator inappropriately called out the student who had reported the educator’s use of the racial slur, which is not acceptable,” Martineau said.

He said the district then began a formal investigation and placed the teacher on leave. School Principal Kathleen Valenti was also placed on paid leave for 10 days this month, the superintendent said.

Valenti could not be immediately reached Friday.

Martineau apologized to parents for what had happened and added that he acknowledged “there were missteps in this process that further complicated the situation.”

He said all personnel matters would remain confidential.

In the nearby town of Southwick, investigators in March announced they were pursuing criminal charges against six teens who they said participated in “a hateful, racist online chat that included heinous language, threats, and a mock slave auction.”

A group on Snapchat was created overnight from Feb. 8 through Feb. 9 by a group of eighth-grade students, according to investigators. During the chat, some participants expressed hateful and racist comments, including wanting to commit acts of violence toward people of color, racial slurs, derogatory pictures and videos, and a mock slave auction directed at two particular students, investigators said.