KILLEEN, Texas – A Killeen substitute teacher is in hot water after duct taping 10 students' mouths shut at Maxdale Elementary School on Wednesday. 

Three other students in the fifth grade class taped their mouths shut as well.

The teacher was immediately removed from the school "as a result of this outrageous and unconscionable behavior," according to a statement from the Killeen Independent School District.

The teacher has not been identified as Child Protective Services were notified of the incident. The district is also working with law enforcement. 

All 13 students are fine and were able to return to their classroom.  

The district did not say what led to the incident.