Short answer: Yes.
Long answer: Still a yes.
It doesn't take a Great Dane and a handful of meddling kids to figure this one out.
Whoever the shooter is, he's going to want to shot as many people as possible and at the same time, create terror in those he's not shooting in the hopes that they wouldn't act against him.
When someone starts to shoot back, it takes the 'fun' out of it.