How old is she and how long have you had her?
It sounds to me like she is just frightened and trying to get across the message that she is not to be messed with.
Placing her is another room is a good idea at least for now.
I have never had a cat that reacted that way though. Most of mine run and hide in a seperate room on their own if strangers come by.
But then two cats of my cats don't run at all. The older alpha female just glares at them with a "don't even touch" me look even though she is a big sweetheart with people and the other young male that wants to make friends with everyone.