Btw I’ve seen lots of people post that the shooting wasn’t real, was a crisis actor, was staged, conspiracy theories from 4chan etc.
That kinda thing has no basis in reality. Somebody died. Multiple people were injured. The local police left the shooter on the roof for two minutes while running around trying to work out what to do - they didn’t have a communication plan. Nobody had secured the roof before the event.
What happened is simple: a series of security failings, and a shooter.