Well that escalated quickly

So idk if anyone remembers but I’ve made posts about my brother living with us before. He’s been here since like January and hasn’t really worked or contributed anything. I tried to be helpful and let him stay since he got a felony charge and lost all of his belongings. Well we were out of town over the weekend and he took it upon himself to invite over Friends and girls that aren’t his girlfriend and do god know what. My brother sleeps on the couch but he’d been in my room and my sons room in our beds so I told him he has to give my key back and go. He got pissy and tried to punch my fiancé in the face so my fiancé pulled out his pocket knife as a warning for my brother to leave. So he finally gave my key back and then Called the leasing office to let them know that my fiancé is living there without being on the lease. My landlord asked how he knows and he send because he was living there too. Then my landlord said “what do you want me to do about it? You broke the law too” so then when I went in to sign some papers she told me that she got a call from him and that she doesn’t care who’s living in the house we just have to maintain a low profile and non of what was going on today.

I’m just stressed to the max because my brother said something about coming back with a gun.

Update: I filed a police report in case he comes back to destroy my car or harm any of us. That’s all I can do