You must trap and shoot them in the trap until they are all gone, and that'll take care of the problem for the season. If you release them, they'll just be back. You can tell when you have exhausted the colony by the ground around the trap. (Be sure to stake the trap down so it won't move.) When there is no more scratching in the dirt around the trap, you've got the whole colony. Their friends come around after one of them is caught and scratch trying to release him.
Make sure your trap is big enough. A friend claimed this wouldn't work. He had a medium sized trap. We took ours over there and caught is coon -- a fellow so large that he was able to reach in my neighbor's trap and eat the food, but the door wouldn't close because the coon's back end was sticking out. My neighbor was just providing midnight snacks for his unwelcome visitor until we loaned him our giant model.