Christchurch Boys’ High School is investigating after a video circulated of a man being assaulted and made to eat pet food outside a fast-food restaurant. 

The video, which was shared on social media on Monday night, depicts the man on the ground, before being dragged out on to the street. 

The group of boys, at least one of whom appears to be in Christchurch Boys’ High uniform, proceed to punch the man to the ground. 

They continue to kick him for some time, before forcing him to eat pet food. 

All of this was filmed and shared on social media. 

It is not clear when the video was filmed. 

Christchurch Boys’ High School headmaster Nic Hill was made aware of the video by the Herald on Tuesday. 

He said the school had been in contact with the police and meetings are under way with students who may have been involved. 

”This behaviour is not on,” Hill said. 

”I’m incredibly disappointed to see it, there’s no excuse for any of this.” 

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Hill told the Herald the school was working with McDonald’s Riccarton as well as the police. 

Detective Senior Sergeant Karen Simmons said police “have received a report of a video depicting an assault and are making inquiries to determine when it occurred and who was involved”. 

“A local high school is assisting with our inquiries,” she said. 

Police advised the public never to “take matters into your own hands”. 

“Instead, anyone with information regarding incidents of concern should contact police immediately, providing as much detail as possible.” 

Christchurch Boys’ is regarded as one of the country’s top high schools. 

Opened in 1881, it has provided secondary schooling to countless future business, community and sporting leaders. 

Its website states it has a history of “educating fine young men”. 

“Christchurch Boys’ High School has a history of over 130 years. We take great pride in promoting the personal, moral and intellectual growth of every boy.” 

Jaime Cunningham is a Newstalk ZB multimedia journalist, based in Christchurch. 

Katie Oliver is a Christchurch-based multimedia journalist and breaking news reporter.