A Grade 10 pupil is in ICU after being stabbed at Waveren High School in Tulbagh, authorities confirmed on Wednesday.
He was stabbed in the upper body during a scuffle behind a building around 12:00 on Monday, when a group of "unknown men" approached pupils, said Western Cape police spokesperson Siyabulela Malo.
Two boys, aged 14, were arrested and released into the custody of their parents.
Police were investigating a case of assault with intent to cause grievous bodily harm.
Provincial education department spokesperson Bronagh Hammond said the assault on the school grounds happened during break.
"Two other learners are involved. The incident is being investigated in terms of further disciplinary action," she said.
"Counselling support was provided to the learners of the school. We sincerely hope that the learner recovers and we await further news about his condition."
In KwaZulu-Natal, a pupil at a Pietermaritzburg high school died after being stabbed this week, while five others have been hospitalised, the KwaZulu-Natal Department of Education said on Wednesday.
While the details around that incident are unclear, it was understood that one of the five injured was in ICU, department spokesperson Kwazi Mthethwa said.