Surveillance room.
After leaving for a while, Principal Hong returned and asked upon entering, "How are things going?"
A few teachers responsible for the surveillance room replied, "Not bad, over a thousand have died already."
Principal Hong frowned, "Only that many?"
A male teacher laughed and said, "That's quite a lot, Principal. How long have you been away? All together it's been less than 30 minutes, and already 100 have died... isn't that enough?"