[FITZ]

issue an arrest warrant

Then don't arrest them, just deport them.

[TheGrimReaper]

Exactly.... deport the bastards.
Revoke their damned student visas, and process them OUT immediately. As non-U.S. citizens, they have no standing with which to claim 1st Amendment rights. Their "speech" could easily be viewed as sedition.
Deportation or incarceration... either works for me.