TMJ4 reports:

One week into the school year, a student has been arrested for attacking a teacher in the middle of class.

Cell phone video captured the exact moments a 16-year-old student went from a confrontation with a teacher to knocking him down and punching him over and over.

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“That scares me. Oh my god, that really scares me,” said Niki Gerth, who has a freshman daughter at South Division High School.

Niki and Jerry Gerth did not know this fight happened at their daughter’s school earlier today until TODAY’S TMJ4 showed them the video.

“It makes me mad,” said Jerry Gerth.

A student from South Divison says the man is well known among kids.

“He is kind of like helper,” said Gustavo Miramontes, 17. “He mostly just like if a kid has a question he will help them out if they are struggling or something.”