Hmmm wonder what's making him start something with the males in both tanks. Hopefully he wasn't trying to "get friendly" with them and they objected LOL. Seriously though was he recently in with the breeding females? Sometimes when a male goes straight from a breeding environment back in with other males they will harrass him because he smells of the females. When I switch out breeder males sometimes the other males will drive him crazy sniffing him madly and bouncing all over him excitedly..."you smell like a girl! you smell like a girl!" sort of thing. Usually it doesn't get into fighting but I did have a male turn vicious on another and almost kill him.

You'll want to take that male out anyways for awhile alone and treats his bite wounds. If he smells like blood or appears weak until he's healed the other rats might well take advantage of that and really hurt him very badly.