Finally got the whole story. They called us down to home room today to tell us. Somebody called the school threatening to kill a student and also requested that they take the kid outside. They took the student and kept him in the office. Then 30min later somebody called in a bomb threat to the school. So they called in all the cops to search the building. Apparently the part about the football field was exaggerated.
I still call bullshit. Bombthreats are reported in local newspapers.