The first shot of the campaign was fired at 5:00 AM on July 16, 1953 when a Nationalist division landed on the island. After three hours of fierce fighting, the Communists' first line of defense was breached, and the Nationalists had succeeded in forcing them into their second line of defense. By the end of the day, the Nationalists had successfully taken the largest port on the island and controlled most of the island. However, the Communist resistance in the few remaining isolated pockets proved to be much stronger than anticipated.