*UPDATE: A 15-year-old has been arrested in connection with the stabbing. Read more below.
A pupil has been stabbed to death at Thuto-Tiro Comprehensive School in Sebokeng, south of Johannesburg, the Gauteng education department said.
Spokesperson Steve Mabona said a pair of scissors was used to stab the pupil.
The incident took place just before midday.
Mabona said Gauteng Education MEC Panyaza Lesufi was on his way to the school.
In a media briefing at the school, department district director Victor Thetha said the incident happened inside a classroom while the pupils were "playing".
During the ordeal, a 14-year-old was stabbed by a 15-year-old, Thetha said.
"From there he was taken to the admin block sickbay where he was attended to. The unfortunate part is that, when the paramedics arrived, he was certified dead," Thetha said.
Police said they received a call at around 10:20 from the school informing them of the incident.
Addressing the media, police spokesperson Captain Fikile Funda said upon arrival the deceased was found in the sickbay.
Funda said a 15-year-old suspect has been arrested and a case of murder is being investigated.
He said the investigation would direct authorities on what their next steps would be.
The department said it will also be dispatching its psycho-social unit to counsel pupils, families and teachers following the incident.
In June a 16-year old grade 8 pupil from Forest High School in Turffontein was stabbed to death outside the school.
Daniel Bakwela died on the scene after being stabbed by Mohammed Mwela, 19. Bakwela was later arrested following the incident at the school.
His matter is before the Johannesburg Magistrate's Court.