Seems the lead attacker worked at the site, so he was aware of the “gun free” status of the building. (They’ll try to spin this as “workplace violence” as a result.) Then again, CA as a whole is largely “gun free”.
There _have_ been attacks at “places where guns are carried and freely accessible”. Thing is, they were stopped almost immediately - so precisely because the attack was stopped by a good guy with a gun, the bodycount did not rise to the definition of “mass murder” and is duly ignored by anti-gun advocates.
Like I said, Darwin award winners.