How do I notify authorities of someone committing Marriage Fraud?

[OCGirlFriday]

My roomate is committing marriage fraud with a Brazilion guy. He and his girlfriend originally lived with my roomate but then moved out when his girlfriend became pregnant. I did not know this moving in, and after I learned it and voiced that I was disgusted by this, I received an eviction notice from my landlord. The apartment and all the bills are in my roomates 'husbands' name in order to fool immigration officials into thinking they're living together. Since then I've also noticed theres an abundancy of Brazillions living in this small complex. When I asked my landlord about this, she said that the husband wanted me out so I had to move out. I argued that this guy didn't even live in our apartment and there's nothing on the lease allowing subletting. She knows about the marriage scam and basically said it's non of our business. I asked about my name being on the lease and she said she never added it. I think something shady's going on - that this 'husband' guy is giving her money to get me out and to be out of their hair. I also believe that she's running some kind of ring (although I can totally be wrong) because of all of the other Brazilian's in this complex. There's a lot of things that seem really shady about this place.

My question is, am I barking up a tree or should I just move out and leave this situation alone? I'm disgusted by my roomate who defrauding our government and doesn't even try to hide the fact that shes doing it by bringing home different guys every night and living off the money she's making from her marriage. ANd she said there's a Brazilian lady working in the immigration office that gave her and her 'husband' insider info on how to fool the authorities. It's rediculous to me to break the law so blatently and not fear getting caught. She needs a serious reality check but is it my business to give her one??

What should I do???

Thanks for your time.

[Mr. Knowitall]

If it were me, I would probably just mind my own business. If you wish to try to report their marital relationship as fraudulent, try the USCIS.