SVT Nyheter Västerbotten has taken part in a film that the teenager is said to have sent to a class chat.

In the film, you see how the person loads a weapon and then shoots out of a window.

The teenager, who is under 18, was arrested on Tuesday.

After questioning, prosecutors decided to let the person go free.

"Regards written and verbal threats"

However, the person is still a suspect.

The case is classified as serious illegal threats and serious weapons offences.

The police would like tips and information from the public regarding the case.

Prosecutor Andreas Nyberg does not want to say how many plaintiffs there are in the case.

- I can say that it concerns students at the school who received written and verbal threats, says Andreas Nyberg, prosecutor.