The attack involved multiple girls between the ages of 12 and 14.
The video shows one of two female students assaulted at Sinaloa Middle School at lunchtime in Novato last Friday, it is now part of a police investigation.
"I think that all she was trying to do was defend herself and she was trying to knock away blocks and stuff but the other three were on top of her going after her and not stopping," said Christina Carroll, who is a parent.
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"They told me it was vicious. They told me that numerous people were recording. They told me it happened very quickly," said Brittany O'Sullivan, also a parent.
Upset parents packed the middle school library Tuesday night looking for answers. School employees called this a horrific attack during that meeting.
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Police say that school administrators learned there was going to be an initial attack here Thursday, but took action and that did not happen.
On Friday, two extra private security guards were brought in and a number of additional administrators. The two district-wide school resource officers weren't on campus though.
"So the school district was aware but the police department wasn't?," asked ABC 7 News Reporter J.R. Stone.
"Correct," responded Captain Sasha D'Amico of the Novato Police Department. D'Amico continued saying, "So if we had been requested as part of our agreement with the school district we definitely would have been involved but that is something we need a request and need information to act on it."
Arrests have been made and police say there could be more. They don't have an answer for why this attack happened.
Melanie Sanchez tells us her daughter was arrested Tuesday after being seen on camera throwing punches. She claims her daughter and others were bullied by the girls who were attacked on video.
"They're being told they're fat, they're ugly, their hair is ugly, balls being thrown at them every single day at school," says Sanchez.
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She says her daughter regrets the attack but snapped, saying even after talks with her counselor nothing was done previously. She's heartbroken that her daughter was immediately taken into custody.
"Hugging my daughter a good-bye when she's never been away from me. That did it. When they took her away today. And I can imagine how the other parents felt when they came back from work and their daughter was gone," said Sanchez as tears fell from her face.
Parents say they want all of these issues addressed going forward.
"The bullying has become a huge problem and I'm hoping that we can address this through this year and for the kids that don't feel safe," says Pam Laidley who is a parent.
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The district says they are paying teachers and staff extra to open their classrooms at lunch so students can come in and feel safe.
Novato Police say they should have more details into the next steps here come Wednesday.
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