During the incident, both students and staff locked themselves in classrooms until the incident was overplayed.
The school has a routine for this, as the staff has prepared for situations like this.
"We have created our own plan for this, to work with the staff on how to act in a sharp situation," says Jan Kristensson, who is part of the school's safety group.
On Wednesday, the day after the incident, all entrances to the school have been locked and the students have been met by staff. The student health service has also increased its staffing and Karlskrona municipality's field group, police and staff from the Church of Sweden have also been on site.
Denies the allegations
The student was arrested by police at the school and is currently under arrest for attempted murder.
- He denies that accusation. He has given an explanation, but unfortunately I cannot go into it, says his defense lawyer Henrik Månsson.
How is he doing today?
"Above all, he is characterized by being detained, it is difficult for most people but perhaps especially for a 15-year-old.