Japanese authorities on Thursday raided the apartment of a nurse who's in custody on suspicion of fatally poisoning at least two elderly patients at a terminal care hospital.
Local media have reported the woman confessed to police she poisoned about 20 patients to have them die when she was off-duty and could avoid the trouble of explaining the deaths to their families.
Kanagawa prefectural police said they searched 31-year-old Ayumi Kuboki's apartment in Yokohama, near Tokyo, for more evidence in the case.
Kuboki was arrested on Saturday on suspicion of killing two men in 2016 by injecting disinfectant into their intravenous drips at the former Oguchi Hospital, since renamed Yokohama Hajime Hospital, a Kanagawa police official said on condition of anonymity, citing department rules.
Prosecutors have more than two weeks to decide whether to indict the former nurse.
The hospital has acknowledged a higher death rate around that time, raising speculation the poisoning may have been systematic and more widespread. In 2016, a hospital lawyer told The Associated Press that 46 other patients had died on the same floor from July 1 until late September that year. It was about a year after Kuboki started working at the hospital.
Around that time, whistleblowing emails sent to the city's health department described problems at the hospital such as a nurse's bottled drink being laced with bleach, a uniform slashed, or missing medical records of patients, according to investigation results published by a city committee last year.
Kuboki, who had left the job since, denied any responsibility when asked about the deaths by Japanese television networks last year.
The case surfaced on Sept. 20, 2016, when the hospital informed police of a possible poisoning after 88-year-old Nobuo Yamaki died while receiving an intravenous injection. Police confirmed his IV solution had been contaminated with a disinfectant.
Police then found there was another victim, Sozo Nishikawa, who died two days earlier. Police got hold of his body just before cremation and conducted an autopsy, which showed he had been poisoned with the same disinfectant.
Investigators have found traces of the same disinfectant only on her nurse uniform, according to the Asahi newspaper.
Investigators also reportedly found tiny puncture marks in 10 of about 50 unused intravenous bags stored at the nursing station on the fourth floor, which handles the terminally ill.
The hospital, which stopped taking new patients and changed its name, installed security cameras and took other safety steps. It also apologized to its patients and families over the alleged crime and the patients' deaths.
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