Coaches fighting

[Dan_ref]

Coach A & Coach B do not like each other (turns out
that A really ran up the score on B a few years ago).
A's a real talker, "And one!" "That's a travel!" "Come on!
Ya gotta call that!" but not out of control, you know the
type. Coach B is loud but only to his players. When he
has something to say to an official he does so quietly
and lets it go right away. So A's bitching & B is defending
his players (and us in the process). A few minutes into the
second half TO is called and instead of the coaches going to
their huddles they start going at each other. Towards the
end of the game it looks like they might actually start
swinging. So (finally!) here's the question: how do you
handle this? This happened in a HS game, but what about
in a college game? Thanks