I was "complaining about" the original poster who didn't call the police for "obvious reasons" and then went on to call a non-emergency line.This is about as good as praying to god for the situation to resolve: it might make you feel good, but does nothing to help anyone.

I have no problem with having mental health workers with cops, but best case scenario for someone threatening random people on the street with a knife is a high dose of sedatives in a relatively-comfortable low-security carceral institution until they age out of violence (and using up resources that could be going to education, affordable housing, and helping young families).

The sooner you get authorities involved, the better chance for this. If they hurt someone (which sounds likely) they will be put in the ACI and probably get stabbed up by higher functioning convicts who don't want to deal with their predatory bullshit.