Ex-nurse suspected of quick murder method

Ayumi Kuboki has admitted to killing Sozo Nishikawa, 88, who died on Sept. 18, 2016, at what was then Oguchi Hospital in Kanagawa Ward, according to the police.

He was found to have been poisoned with a surfactant compound. Kuboki told them she injected disinfectant into intravenous drip bags used to treat about 20 patients, according to investigative sources. Beginning about six months before Nishikawa's death, a series of suspicious incidents occurred at the hospital.