Officers arrested a 16-year-old local youth last night (25 February 2013). He remains in police custody as enquiries continue.
The youth was also arrested on suspicion of exposing himself to another student on the same night.
Any witnesses to the incidents which occurred on the evening of 27 January 2013 are urged to come forward with information.
Anyone with information that can help officers with their enquiries is urged to contact North Yorkshire Police on 101 – select option 2 – and ask for York CID.
If you wish to remain anonymous, Crimestoppers can be contacted on 0800 555 111.
Please quote reference number 12130015430 when passing information about this incident.