Oh come on - It’s trivially easy. Just send some agent provocateurs into the crowd. Start some fights. They can dress up like stereotypical anarchists or students.
The government then has to send troops in to “restore order”.
Issue press releases about the “violent protesters”. Fox News will be a big help here.
Announce that you must sadly enforce a curfew, entirely due to the “violent left wing radical protesters”
It’s so simple.