A Milwaukee high school student has been caught on video beating up his teacher in the middle of class, police said.

The shocking cellphone footage captures the moment the 16-year-old lunges at his teacher, punching him and knocking him to the ground, and then continues the beating.

The South Division High School student and teacher can be heard yelling unintelligibly at each other just seconds before the first punch is thrown.

Police say the teacher’s injuries were not life-threatening and that they arrested the student, who could face possible charges of battery, local station Fox 6 reported.

A Milwaukee schools spokesman said the district is cooperating with police.