According to Region Skåne, the man is in his 50s and his injuries are considered minor. The police expect to be able to conduct interviews at the hospital.
It is unclear what was behind the stabbing, which was carried out indoors.
The boy we suspect of this had left school. He was found outside the school grounds and taken into custody, says police spokesperson Leif Fransson.
The boy himself waved to a police car as it drove by and identified himself. He has been taken to the police station.
He is allowed to sit outside in public areas with an adult while waiting for the guardian and social authorities to arrive before we can talk to him, says Leif Fransson.
Parts of the school were initially cordoned off while police investigated whether more perpetrators were involved.
The knife has been seized.
