From what I remember, it’s been a while, but it was a group of guys (I wanna say an Italian/Irish mob?). But 2 main scenes pop in my head. First being the bartender who they are probably the closest to, was cleaning up at closing and another gang comes in and beats him (to death I believe). They plan on revenge after that. Then I remember the end scene of them in a small circular area encompassed by houses or apartments. It started of slow motion in the rain and the two gangs slug it out.