Gun background check... people unqualified... (Minneapolis)

"If you see something - say something.
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" So who do you contact when you know someone is mentally incompetent to possess a gun? I know a guy who has a carry permit who's bat shit crazy , lives in his van, is a drug user and has pulled his gun on people that he should not have.
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don't tell me to call 911 or the police.
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there needs to be another level of bureaucracy to deal with people like this .
Calling 911 means "what is the address of your emergency?