need advice on handling a student...

[muziq]

Ooof, that's a mine field. Get your campus' counselor involved pronto; I assume your school district also has a main/superintendent's office-level intervention officer, to whom I'd go if the campus counselor is not available. Those folks are professionals (most of the time) and should have initial strategies to employ. Short of knowing more specifics about your school district and its administration, I say get those folks involved immediately.