[JapanCase] The disappearance of Mai Ishii
On July 25, 1991, a child disappearance case occurred in Funahikimachi, Fukushima Prefecture, Japan. This case is considered one of the "three major unresolved child disappearance cases" in Japan. It remains one of the few cases where a strong suspect is identified, though it remains unsolved.
On that day, the house of Kenichi Ishii, a construction worker, was filled with his parents, wife Yoshiko, two sons Kento and Leo, daughter Mai, Kenichi's niece, her boyfriend K, and two daughters of Yoshiko’s friends. In the afternoon, Kenichi’s parents went to karaoke, and Mai and the other two children spent time playing games in K’s room. At around 10:30 PM, Yoshiko entered the children’s room to cover them with a blanket. Then, she went to the second-floor bathroom, where she saw K leaving the house. She didn’t think much of it and continued with her bath. Afterward, she heard a sound of a door closing and someone climbing the stairs, but she didn’t investigate further. She finished her bath and went to bed in the room where her husband and children were sleeping.
At 2 AM, Kenichi’s parents returned from karaoke and found the front door unlocked. They realized that K was missing, but Kenichi, still half-asleep, brushed it off and went back to sleep, saying they could talk about it later. Around 5:20 AM, the two children who had slept with Mai woke up and discovered that Mai was gone. They immediately told Kenichi and Yoshiko, and the family soon realized Mai had disappeared. The police found no fingerprints or traces of anyone who was not part of the family, leading to the conclusion that the kidnapper was likely one of the family members or someone who left no evidence.
Mai, being a timid child who was afraid to go to the bathroom alone at night, would not have left the house on her own. The police concluded that someone must have taken her while she was sleeping. When the police dogs were used to search the house, they stopped at the front door, indicating that Mai had been waiting near the door to be picked up by a car. A white car was spotted near the house around 11 PM, but it disappeared the next morning, and despite checking with local car owners, the car’s owner was never identified.
The police initially considered Yoshiko and K as suspects, as they were the only ones awake at the time. While Yoshiko was quickly cleared of suspicion, K became the focus of the investigation. K claimed he had left to meet a friend in Koriyama city, but his actions were deemed suspicious by the police. K was investigated for two weeks but was eventually released when an alibi was established, and the taxi driver who had taken K to Koriyama confirmed his story.
However, some internet forums in Japan, like 2ch, strongly pushed the theory that Yoshiko and K had conspired to kidnap Mai. Yoshiko's behavior that night was suspicious. She claimed to have heard someone entering the house and climbing the stairs, yet she didn’t check or lock the door. At that point, the only adult awake in the house was Yoshiko. Some argue that the kidnapper was likely someone from the family, and that Yoshiko may have been involved, or at least knew about K’s actions and covered for him.
Two months after Mai’s disappearance, Kenichi and Yoshiko received shocking testimony from the children who had been with Mai. The children said that K had asked Mai if she wanted to go out at midnight. They reported this to the police, but the police dismissed the testimony, claiming the children were confused. Kenichi later followed K but was unable to gather any concrete evidence.
Mai's parents continued to search for her and appeared on TV to raise awareness, but they received no substantial leads, only prank calls. They held onto the hope that Mai would return someday and did not move, but in 2015, they finally moved out, realizing that Mai was unlikely to ever come back. The case remains unsolved, with many questions still unanswered.
