ARNHEM, Netherlands -- A Dutch court has convicted a 15-year-old boy of murdering a teenage girl after she argued with another girl on a social networking site -- a case that shocked the Netherlands because of the age of the killer and his victim.

Arnhem District Court on Monday sentenced the youth, identified only as Jinhua K., to one year in prison -- the maximum punishment for a minor. Judges also ordered him to undergo psychiatric treatment at a juvenile detention center for three years.

Judges say K. stabbed to death 15-year-old Joyce Hau at her home Jan. 14 and then attempted to kill her father.

Prosecutors have charged the girl Hau allegedly argued with and another boy with arranging for K. to carry out the stabbing.

Dutch media dubbed the case the "Facebook slaying."