An investigation is underway into a suspected murder of an 88-year-old man who died from poisoning at a Yokohama hospital earlier this week while being administered a medical drip as well as three other suspicious deaths at the same facility, police said Saturday.
Nobuo Yamaki died about an hour after his falling heart rate triggered an alarm at Oguchi Hospital in Yokohama's Kanagawa Ward around 4 a.m. on Tuesday, according to investigators. Hospital staff notified police that a foreign substance might have been put into the drip, which the police confirmed without identifying the substance.
A nurse in charge of the patient changed the drip around 10 p.m. on Monday. As there were no apparent holes in the bag, the police suspect someone may have used a needle to insert a poisonous material.