The children are suspected of having committed or planned acts on behalf of criminal networks.
At least 16 of them had been in contact with the relevant social services before they were recruited, and at least twelve of them were living in an institution when it happened, the survey shows.
Many of the children were recruited by the Swedish Foxtrot network. The network has received significant attention in Norway in recent months, where boys as young as twelve have been linked to acts of violence that police say were ordered by Foxtrot.
