I'm sure a normal bazooka can do the job as well, but freeze and then smash the Clown into piece sound more satified, I guess...
But for real...how the police can be don't have any lead ? School don't know who they hired as clown ? And his clown face is just his face with some paint job, and they even have someone saw his face without make up....but then again, why I'm keep surprise and question ??