I would definitely call the police. Although thesevare public places they do not have the right to violent activities within private property. At least this will make the homeless person think twice before he dies he same thing to someone else.
I know of one volatile man in Napa that carries a knife. Be careful.
I'd say "sorry you're angry sir,is there a way we can take care of this situation,so you are not upset?" If there's not I would involve management. Best of luck
Call 911. Some of the homeless guys carry mace.
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