We had upstairs neighbours who did exactly the same thing, at all hours of the day, so I can sympathize with you. I had to walk around the top floor a bit to figure out where it was coming from, but that didn't wake long. If you feel comfortable enough, that may be a good way to figure out exactly where the noise is coming from.
For your own safety, I'd recommend not confronting them directly. That kind of behaviour suggests instability, and there is a good chance that they could turn their anger on you. (This was the advice give to me by my father, who works for a child and family services organization, so he saw thing kind of thing all the time and has seen how it can escalate.) I'd say contact the building manager and the landlord, and then the police. Even if the fight has settled down before the police arrive, they should at least make an enquiry to follow up on your complaint.
Good luck with whatever you decide to do. I know what an unpleasent situation this is to be in, and I hope it all works out for you.