That's actually my old range where that happened. In my opinion, a first rate place.
I, the range officer and another customer got swept by a new lady shooter with her Glock - finger on the trigger. Turned toward us, pointing it straight at us, and saying "I don't know what to do next". We all 3 hit the ground in front of her. She couldn't figure out why we were so upset.
So that others may learn.