Need to break a lease and need advice?

We moved into our apartment at a complex back in January. We've never lived in a complex it's always been houses or duplexes. Shortly after moving in we noticed drug activity in an apartment below us. We were gone over mothers day weekend and came back to some craziness. The apartment with the drug activity had a shooting over the weekend in the apartment. We also had new neighbors move across the hall from us and noticed right away some more drug activity. The lady who does the leases told us when we signed that she screens all potential tennants to keep out problem people. Obviously she has not done this as the shooting suspect who lived there had a lengthy criminal record according to the paper. We have decided enough is enough and want to move back to our hometown when I find a job. Do we have any legal rights to break the lease or demand a month to month change to the lease since we were decieved into thinking it was a safe place to live? Please any honest advice is needed.