When they went to the initial murder/shooting scene there was no gun. That would mean no murder/suicide and would mean the murderer was still on the loose, with a gun.
When people are found shot to death, especially in a school environment, that should be more than enough cause for alarm.
When people are found shot to death, especially in a school environment, that should be more than enough cause for alarm.
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As I understand it, the question is not whether people were alarmed.
The question is whether persons in charge could have done something to prevent the second crime.
So far, all of the suggestions I have seen would only have scattered the cops all over the place and thus diluted their ability to do their real job, which is to identify and pursue the murderer, and without any benefit to anyone.
That guy was going to kill all he could. If not where he did, somewhere else.