McIvor said it was “disturbing and disappointing” the video had circulated on social media.
The father of one of victims said his son now “freaks out” whenever he goes to South Dunedin.
“My son is in a bad state psychologically ... and I don’t really know what to do about it.”
The cause of the conflict was school rivalry, the father said.
“It was originally just a spat between two guys from two different schools.”
The attack occurred after an organised fight between two teenagers at a nearby property.
The father said the organised fight was between his son’s friend and a King’s pupil and the incident resembled a “fight club”.
“There was another video circulating at the young lad’s place.
“There was quite a gathering in the video I watched — all King’s High pupils gathered around on both sides of the fence so the neighbours couldn’t see in.
“It was quite well done. They’ve obviously done it before.”
The man said his son was left embarrassed after the video circulated around the two schools involved.
“It’s freaked him out quite badly.
“I’m going through a lot of petrol at the moment as he won’t even take the bus around South Dunedin any more.”
Following the incident, the school, pupils and parents involved had a series of meetings.
The father said he got the impression King’s wanted them to forget it ever happened and write it off as schoolyard antics.
“Last time I was there was with the deputy and the rector.
“The deputy did all the talking, and said ‘don’t worry about anything. We will keep you in the loop with everything and give you a call next week’.
“After the holidays he just never contacted me, and never called, so I called to say how displeased I was.”
McIvor said when the father contacted the school on September 7 he was invited in immediately and the school kept him updated about the investigation.
“We conveyed to the father from the outset that we would be dealing with this incident as a serious matter, but that we could not and would not be able to provide specific details around other individuals, given we are dealing with minors, and also that we had to maintain the privacy of those involved.”