The Kyoto Shimbun learned from police sources that the first criminal investigation section of Kyoto Prefectural Police and others arrested Yoshikazu Okubo, a respiratory physician from Sendai City, Miyagi Prefecture, and Naoki Yamamoto, a doctor from Tokyo, on suspicion of murdering a woman in Kyoto with amyotrophic lateral sclerosis (ALS) through administration of a drug at her request. ALS is an intractable nervous disease that progressively impairs control of the muscle throughout the body.

This was the first case in 12 years in which doctors were arrested or had papers pertaining to a case sent to the public prosecutor's office for "euthanizing" a patient. The previous case occurred in 2008, when criminal papers were sent to the prosecutor's office for an alleged homicide committed by an ex-chief surgeon of Imizu Municipal Hospital, Imizu City, Toyama Prefecture, although he was not prosecuted due to lack of evidence.

According to the investigators concerned, neither Okubo nor Yamamoto were the victim's doctors. Seemingly, they met through a social networking service (SNS) and had not been actually acquainted with her.

A police source explained that, allegedly, Okubo and Yamamoto received a request from Yuri Hayashi, an ALS patient living in Nakagyo Ward, Kyoto, and visited her at her apartment in Kyoto City on the evening of November 30, 2019, to cause her death by giving her medication in the room.

After two suspicious men, believed to be the suspects, visited her apartment, Hayashi's physical condition suddenly changed. She was transported to a hospital where her death was confirmed. A drug that she had not usually taken was detected in her body. Reportedly, the Kyoto Prefectural Police investigated the case and identified the two suspects from security camera footage and other sources.

According to sources, the woman developed ALS around 2011. Just prior to her death, she was unable to speak or move her limbs. She lived alone while receiving 24-hour general daily living care by helpers for the severely impaired. The home-visit nursing care was provided as a welfare service for people with disabilities.