COPENHAGEN, Denmark (AP) — A Danish prosecutor says she is appealing a six-year prison sentence given to a Danish teenage girl convicted of attempted terrorism, saying she should be incarcerated in a mental institution instead.

Natascha Colding-Olsen, now 17, was found guilty earlier this month of planning bomb attacks on her former school and on a Jewish school in Copenhagen, and of possessing chemicals, two years ago.

Prosecutor Lise-Lotte Nilas said Wednesday the case was “totally unusual and serious.” Earlier a medical report concluded that the girl was dangerous to others.

During her trial, Colding-Olsen, who converted to Islam in 2015, admitted the plans and making contact with people whom she thought were radical militants.

It was not clear when the appeals case would start.