Condemnation of students who attacked a boy and the others who watched on at Darfield School.
A video of the boy being pushed then punched and kicked while he is on the ground has been widely shared.
It was shared by the boy's sister, who posted it on her Facebook page to raise awareness of bullying.
She wrote that "there is absolutely no excuse for this, attacking a kid from behind so hard it knocks him out." Police are investigating.
Two Year 10 students have been stood down as a result and will attend a Board of Trustees disciplinary meeting.
Darfield Principal James Morris says the school is appalled by the behaviour.
In a letter to parents, he said they're offering the victim support and a complaint has been made to police who are now investigating
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