Alarming footage posted on Facebook shows pupils jeering as a schoolboy gets punched and pursued by his teenage attacker while trying to get away.
The shocking incident at Canterbury Academy yesterday has been condemned by the victim's parents who say this kind of bullying behaviour has got to stop.
In the recording, which Kent Online has taken the decision not to share, several pupils can be heard shouting "hit him" before the 14-year-old victim is punched, causing his glasses to fall off into his hands, before he attempts to get away.
But the boy is followed by his attacker and dozens of other jeering and shouting children.
He is then hit again before the crowd disperses when members of staff step in.
The victim's devastated parents Paul and Tara Amos, who live in Sturry, say the worst part is seeing the footage and hearing other children clapping and egging on the attacker.
"The cheers and the clapping - it makes me feel sick," said Mrs Amos.
"And it's disgusting that people were filming it. If they were my kids they would be in so much trouble.
"I'm constantly telling my kids 'don't make other people feel how you wouldn't want to feel'.
"Watching the footage is so upsetting. As a parent you don't want to see that."
Mr Amos says the pupils cheering in the 52-second footage should be made an example of and suspended from school.
"This has got to stop," he said.
"It's so sad that bullying isn't noticed until there is violence.
"When you send your kids to school you put them in the care of the school. That kind of thing doesn't happen at home, so why is it happening there?"
Mr Amos says his son is surrounded by a loving and supportive family but some children may not have that.
'This is serious. Something needs to be done to stop it' - Paul Amos
"They might go straight up to their bedroom and self-harm or kill themselves," he said.
"This is serious. Something needs to be done to stop it."
Jon Watson, executive principal of the Canterbury Academy, says staff intervened and resolved the incident in less than a minute.
"The school takes an incredibly dim view of any incident involving violence and, as such, the incident has been dealt with swiftly and severely in line with school policy; a policy which can see students excluded from school and even permanently removed," he said.
"Furthermore, the school does not condone the videoing of any incidents and for any pupil who does this they too will face sanction, as will any student who can be identified as encouraging violence in any way."
It is understood the attacker has been suspended and a pupil who filmed the incident has been sanctioned in line with school policy.
In November, shocking footage of Charles Dickens School pupil Evee-Anne Cooper being attacked was circulated widely on social media.
Pupils who shared the video or left unacceptable comments were suspended or excluded.
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