第五福竜丸
A Japanese fishing boat, "Daigo Fukuryū Maru" (Lucky Dragon No.5), came in direct contact with the fallout, which caused many of the crew to grow ill due to radiation sickness. One member died of a secondary infection six months later after acute radiation exposure, and another had a child that was stillborn and deformed. This resulted in an international incident and reignited Japanese concerns about radiation, especially as Japanese citizens were once more adversely affected by US nuclear weapons. The official US position had been that the growth in the strength of atomic bombs was not accompanied by an equivalent growth in radioactivity released, and they denied that the crew was affected by radioactive fallout. Japanese scientists who had collected data from the fishing vessel disagreed with this.