Fukuryu (Japanese: 伏龍, Hepburn: Fukuryū) (also known as suicide divers and kamikaze frogmen) were a part of the Japanese Special Attack Units prepared to resist the invasion of Japan's Home islands by Allied forces. Six thousand men were planned to be trained and equipped with diving equipment for the role. They would use attack mines affixed to bamboo poles. Plans also included reinforced concrete stations to protect men from the explosions. Only twelve hundred men had been trained when Japan surrendered before the invasion of the Japanese mainland occurred.