A Rosehill College student has filed a police complaint over a large fight that involved a gang-affiliated parent on the school grounds.

A brawl broke out yesterday allegedly involving 150 people, including parents fighting students.

The South Auckland school went into lockdown during the incident as police responded in large numbers and sickening footage of the violent brawl emerged on social media.

Police have confirmed that one of the parents allegedly involved in yesterday's incident has been identified and is affiliated to a gang.

"He has been trespassed by the school and spoken to by Police," Inspector Tony Wakelin said.

"This has of course been intimidating and students and parents are rightly concerned.

"Police have met with the school principal this morning and we are working closely with the school to address these issues."

Previous incidents have not been reported to police, Wakelin said, and police are actively encouraging anyone with concerns to contact Police.

"This type of behaviour is completely unacceptable."

The father of a Rosehill College student fears he may have to move her to a different school to escape constant violence.

Today, Rosehill College students were filing into school for the last day of the week with one notable change at the entrance to the school, two security guards.

The Herald has confirmed the security guards are not commonplace at the school.

It appeared to be a routine day as parents and caregivers dropped off students and others walked to school in the rain.

The man who spoke to the Herald asked to remain anonymous.

His daughter was familiar with the constant fights going on in and around the school, he said.

"My own daughter was attacked here a month ago. A gang of girls broke her nose, the teachers couldn't do anything."

She was taken to the school clinic to be cleaned up and was followed by the same girls who tried to kick the door in to get to her, he said.

"It seems that the kids have control of the school."

Fights at the school were commonplace, he said. When waiting at the dairy down the road to pick his daughter up he would often see fights with uniformed students at a nearby church.

"I had an interview with the head of deans and told him there was no security here. I turn up today and there is two little security guys, there are 50 kids fighting in here, it's terrible.

"It's like a pack of animals. I'm very concerned I don't think they have control of these kids, something has to be done from the top."

He said yesterday there had been two big brawls, each with over 50 students.

"My daughter said there were kids with teeth falling out, blood everywhere. The teachers can't do nothing about it they just stand there shaking their head."

The incident which saw her daughter's nose broken was because she was defending her friend who had been targeted by several students.

"Her parents took her out of the school; we might look at doing the same thing for our daughter."

"As a parent this is not the environment you want your kids to be growing up in."

He had other children who would start high school next year and he didn't think he would take them to Rosehill College.

"They've decided to hire two security guards, I mentioned this a month ago, two security guards isn't enough.

"They need cameras, they need 10 security guards, there are over 1500 kids in here. How are two security guards suppose to control these kids.

"I'd like to see security amped up, I'd like to see security cameras which prevents kids getting up to mischief. They can also see what is happening if they have a control centre."

A parent of a student at the college who was too scared to send his daughter back to class yesterday told the Herald the fight was believed to be in retaliation to another fight between two male students on Wednesday.

"There was a big fight yesterday and one kid in particular got bashed over, then his parents came down with weapons to the school today, basically as retribution I am guessing."

An anonymous student said he was locked in the nurse's office when the incident occurred.

"There were kids crying and having panic attacks and afterwards people were coming in with blood on their shirts and stuff."

He said there were people with broken noses, and hands and some suffering from concussion, though a St John ambulance spokesman told the Herald he had no record of a callout to the school.

Rosehill College principal Sue Blakely said in a statement sent to parents and caregivers the school went into lockdown "as a precautionary measure".

"We went into lockdown and called for police assistance when we had some unauthorised persons on site at lunchtime. The police were satisfied there was no further concern."