Hi,
It seems the suspect(s) have cased the joint well enough to know the security layout, the personnel on premises, their schedules, etc. It was well-planned. I'll wager the gang has moved on to another county or state to continue this madness.
Chances are, if the perps are caught and cornered they will not go quietly. Despite the attitudes of some people regarding crime, if the bad guys resist with lethal force I'll find it no great loss if they end up being well ventilated by the local authorities.
The attitude of "blaming society" instead of blaming the criminal has caused this terrifically tragic upsurge in violent crime all across the country. There is no longer punishment. There is no longer a deterrent. Soon there will no longer be a civil society.
Lord have mercy on us all.
Thank you for your indulgence,
BassCliff