That happenned to me once. Unless you have some big spells I would say you were SOL. I would leave town, hit them hard and then re-enter town again right away, heal up, and then do it again until they were dead.

The mantraps have followed me to the gate of Ishad n ha and when i go out the gate they are there , needless to say my party gets munched before i can run or fight, any ideas ?