A 14-year-old boy has been arrested for allegedly attacking another pupil at their Sham Shui Po school.

Video circulating online purportedly shows a student of the Kowloon Technical School kicking and throwing another boy to the ground inside a classroom.

Police said they arrested a suspect over assault occasioning actual bodily harm on Tuesday night.

The alleged victim, 13, went to the Caritas Medical Centre due to pain in his waist. Officers said his injuries were not serious.

The Education Bureau said the school has set up a crisis working group to handle the incident, and that it will be in close contact with the school and offer assistance if necessary.

The bureau added that it has a zero-tolerance approach towards bullying and will follow up on such cases in a serious manner.