A father of a Glenfield Intermediate School pupil has taken to social media to share a video of the moment his son was attacked by school bullies.

The video, taken by school students and posted online last night by the victim's father, shows two kids attacking the boy outside the Auckland school.

Screams are heard as the 11-year-old is pushed to the ground multiple times, just before his father speeds up in a van and stops the fight.

The father, who wished to remain unnamed, told the Herald he was extremely angry when he pulled up to find his son at the mercy of a group of bullies.

"The brakes were screeching as I pulled the handbrake up and jumped out straight away knowing it was my son underneath.

"I walked up to the kid and grabbed his bag, and said 'you are coming with me to the office'.

"The principal came running out and asked me to quieten down, but my son had just been beaten," he said.

The victim, a Year 7 pupil, started at Glenfield Intermediate this year, and his father said the first case of bullying happened a few days into the term.

"This kid came up to my son and asked him to get out of his chair, despite the fact there is no set seating in the class," he said.

"My son replied 'make me', so this kid threw all of his stuff on the floor. My son then punched him in the stomach and the kid punched my son in the face."

Mark Whitford, principal of Glenfield Intermediate, said the school takes all matters of this nature "very seriously". (Photo / Michael Craig)

After this incident, the father said his son came home "terrified and absolutely scared to go to school".

"After that we went to the school and had a chat, and they promised us nothing would happen again," he said.

Two weeks later, the father said the bullying has got out of control and is being "swept under the carpet" by school authorities.

"The principal asked me to leave the matter with him, but after stewing on this last night I decided I had to take it further because this is unacceptable.

"What does it take before the police or the school does something about these children who are causing the problem - does my child have to get killed?"

He said he went to police to try and lay charges, but was advised this was not possible and a report was taken.

Despite a visit to the school today, he is yet to hear what measures have been taken to deal with the situation.

Mark Whitford, principal of Glenfield Intermediate School, confirmed he was aware of the incident.

"Our school takes all matters of this nature very seriously," he told the Herald.

"In regards to the incident, we are following all processes to resolve this matter and can confirm that the health and safety of all our students is our priority."

The father said his son did not attend school today, after receiving a concussion test at A&E and being advised to stay home.

He said he would like the students involved to be expelled from the school.

"Bullying should have a zero tolerance. If it carries on and on then they should be expelled straight away. It is getting out of hand," he said.

"My son has been bullied a lot since primary school. I was happy to get him out of his last school because I thought the bullying would stop. But then it started up all over again.

"It is crazy. Somehow it has to come to an end."