A substitute teacher has been banned from the campus of an elementary school in Texas after she allegedly placed duct tape over the mouths of 10 students as punishment.

The incident happened when the teacher, who was not named, was substituting a fifth grade classroom at Maxdale Elementary School in Killeen on Thursday.

According to reports, three other students also put duct tape over their own mouths "as a result of the substitute teacher’s actions." 

"The substitute teacher was immediately removed from the classroom and barred from the campus as a result of this outrageous and unconscionable behavior," the Killeen Independent School District said in a statement, ABC News reported.

The incident lasted for several minutes, officials said. Carmello Brooks, one of the students whose mouth was allegedly covered with tape, ripped it off from over his mouth only to find the teacher put another strip, according to his mother Adaeze Akudolu.

CBS affiliate KWTX-TV quoted chief communications officer for the Killeen Independent School District, Terry Abbot, as saying: “As soon as school leaders learned of this incident, all 13 students were taken to the school nurse for observation and any treatment necessary."

All of them were deemed well enough by the nurse to continue at the school for the day.

The teacher had joined the the school district in January 2016, Abbott told ABC News. It is unclear if she had substituted at Maxdale Elementary School in the past, Abbott said.

Child protective services were also informed of the incident, ABC reported. School officials "don't know why she did it at this point," Abbott said.

“The leadership of Maxdale Elementary School and the Killeen Independent School District are deeply saddened by this event,” the school district’s statement further said. “The principal has informed parents, and has reassured parents that the staff will continue to work hard to make sure every child at the campus is absolutely safe every day.”

In a similar incident in St. Louis County in Missouri in August, a teacher allegedly duct taped a seventh grade student to her chair because the child was not listening to her instructions to stay in the seat.

The teacher at Central Middle School in the Riverview Gardens School District was placed on administrative leave after the incident, district spokeswoman Leata Price-Land told the  St. Louis Post-Dispatch.

“We are just as disappointed about the issue as everyone else is, so we are right now trying to get the details about everything,” Price-Land told the newspaper. “Whatever occurred, this isn’t part of our value system.”

The same month, a 4-year-old girl was allegedly duct-taped to a chair at a day-care center in Florissant, Missouri.

The parents of the child, Elysha Brooks and Christian Evans, told Fox News affiliate KTVI  that they learned of the alleged incident after the Missouri Department of Children and Family Services sent them a picture that appeared to show their daughter restrained in the chair.

At the time of the incident, Evans said: “Seeing your child duck taped to a chair, seeing the anxiety, seeing how scared your kid is, knowing for one that you’re not there to protect them, and knowing for two that you have people around that would stoop to that level to even hurt your child puts you in a crazy mind state,” KRON4 reported.