At least these LE learned not to be wusses like the ones at Columbine.
Some students in lockdown in gym. Some are leaving or have left.
To be fair to the LEOs from Columbine, they were not trained to handle an active shooter situation.
Now almost all P.D. have this training, and it is because of the hell that the community of Columbine went through, that we get that training now.