At night , the Japanese left their defenses under cover of darkness to attack American foxholes , but U.S. Navy ships fired star shells to deny them the cover of darkness .
There , the Marines were ambushed by Japanese troops who occasionally sprang out of tunnels .
At night , the Japanese left Japanese 's defenses under cover of darkness to attack American foxholes , but U.S. Navy ships fired star shells to deny them the cover of darkness .
There , the Marines were ambushed by Japanese troops who occasionally sprang out of tunnels .