The official account of how a gangster died during questioning at a Yokohama police station in 1997 is being challenged in court by the victim's daughter, who says Kanagawa Prefectural Police are hiding crucial evidence that could disprove the alleged suicide.

On Nov. 8, 1997, a handgun was fired at around 2:50 p.m. inside an interrogation room of the Tobe Police Station in Yokohama's Nishi Ward, taking the life of Yoshio Yanagi, 55, who was arrested 18 days earlier on suspicion of illegal possession of the weapon.

Kanagawa police reported to the National Police Agency that Yanagi, a former gangster who ran a financial firm in Yokohama, had taken the gun and a bullet -- both placed on the table as evidence in the case against him -- and shot himself in the chest. Yanagi was pronounced dead 30 minutes later at a nearby hospital.