Saito and his crew used high-end camera equipment like long-focus telephoto lenses to film women bathing in the open-air hot springs, the Japanese police told The Asahi Shimbun. The men would take these pictures while hiding in mountainous areas several hundred meters from the springs, the police said. The group would also get tips from Saito on how best to photograph the women, and hold gatherings to view the footage together. Yutaka Seki, an executive director at the Japan Hot Springs Association, told the SCMP that while photography and filming are prohibited in hot springs, new technology makes it difficult to fully prevent such cases from happening.