In real life most of the survivors were sent to Japanese prison camps but 98 civilian construction workers were held on the island to help the Japanese with their defenses. After the Americans conducted a successful air raid in October 1943, the civilians were machine-gunned to death. A lone survivor escaped and later carved a message on a coral rock on the mass grave where they were hastily buried. He was later captured and beheaded. When the island fell in 1945, the commander responsible for the massacre was executed.