Both the suspect and the victim are minors and students at Sampo School, which hosts grades 1 through 9, or pupils from ages seven to 15. The school is located in the district of Kaleva, just outside the centre of Tampere.
The Central Finland Police Department announced via their official Twitter account that they suspected one young pupil attacked another, but that the suspect was now in police custody and the situation at the school was safe.
Police in Tampere were called to the comprehensive school at 8am on Thursday morning after receiving reports of a violent incident involving a sharp instrument or blade.
Tuija Viitasaari, Head of Education for the City of Tampere, told the local newspaper Aamulehti that school work would continue as usual on Thursday.
"A bulletin has been sent to students’ homes as per police instructions. This is an isolated act of violence. School work is safe at the moment and the school day will continue as normally," Viitasaari said.
She added that crisis work started immediately after the incident this morning, and a crisis team -- including a psychologist, a counsellor and a nurse -- would visit classrooms to speak with students.
"We will answer their questions as much as possible so that each child understands what has happened. We have instructions on how to deal with such events," Viitasaari said.