How to delete contacts mistakenly added to a list via file upload ?

By mistake, about 1K contacts were added to a list via a file upload. How can they be deleted ? (I thought about uploading the contacts again to a new list, then deleting the new list/contacts; However contacts which ore on other lists aren't deleted). (I would have thought there would be a simple solution, but some searching hasn't found an answer). Thanks Bill Meier