More than a dozen were shot down on the first day of the invasion by scared, trigger-happy soldiers, kids, most of them, who pursued the Tommyknockers from house to house. After a while, some of the invaders' fear began to rub off. By afternoon they were actually having fun-they were like men driving rabbits through wheat. Two dozen more were killed before the Army doctors and Pentagon brain-trusters realized that the air outside of Haven was lethal to these freak-show mutations who had once been American tax payers. The fact that the invaders could not breathe the air inside Haven would have seemed to have made the converse self-evident, but in all the excitement, no one was really thinking very well (Gard wouldn't have found this very surprising).