Police in Tonga say if fighting between schools does not end, this year's intercollegiate sports competition will be cancelled.
In the most recent violence at the weekend, involving students and ex-students of Tonga College and Liahona High School a bus and a police car were damaged.
Students have been arrested and are facing charges for causing damage to public property.
Police say there have been clashes each weekend since school resumed this year.
The deputy police commissioner, Salote Tonga, has told Radio Tonga that if the violence does not stop police will push for the colleges' sport competition to be cancelled because it would not be safe to stage it.
She says these brawls are caused by just a few but all schools in Tonga will bear the brunt.
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