Police in Japan are investigating whether a serial poisoner is responsible for killing as many as 48 elderly patients by injecting disinfectant into their intravenous drips.

Suspicions began after an autopsy showed two elderly patients had been poisoned in Oguchi Hospital, Yokohama.

Sozo Nishikawa and Nobuo Yamaki, both 88, died on 18 and 20 September respectively, after having a drip administered.

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Investigators found 10 unused intravenous drip bags with small holes in their rubber seals on the fourth floor of the hospital, where the two elderly patients had died, The Japan Times reports.

Police believe the suspect may be an insider with medical knowledge.

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EPA 40/50 1 August 2019 Palestinian men breathe fire on the beach as entertainment for children during the summer vacation in Gaza City. AFP/Getty 41/50 31 July 2019 A woman rows a boat through the lotus plants on the waters of Dal Lake in Srinagar, the summer capital of Indian Kashmir. The lake is a popular tourist destination because of its floating gardens and lotus flowers. EPA 42/50 30 July 2019 An effigy of demon Ghantakarna is burnt to symbolize the destruction of evil and belief to drive evil spirits and ghost, during the Ghantakarna festival at the ancient city of Bhaktapur, Nepal. Reuters 43/50 29 July 2019 Hundreds of hot air balloons take part in the Great Line at the Mondial Air Ballons festival, in an attempt to break the 2017 record of 456 balloons aligning in an hour during the biggest meeting in the world, in Chambley, France. Reuters 44/50 28 July 2019 Anti-extradition bill protesters with umbrellas attend a rally against the police brutality in Hong Kong. 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This is to coincide with his state of the nation address in Manila. AFP/Getty

They are now also investigating the deaths of 46 elderly patients since July, who were being treated on the same floor as the two deceased men.

Hospital staff told the newspaper there had been no outbreaks of infection which could account for the deaths.

The two patients died around a lightly staffed three-day public holiday. The entrance to the hospital was locked and guarded at night.

Last month, a staff member’s lips became blistered after they consumed a drink that may have been laced with bleach, The Japan Times said in another report.

It is unknown whether the incidents are related.

The investigation comes two months after the killing of 19 people at a facility for the disabled near Tokyo.</s>Police in Japan are investigating whether a serial poisoner is responsible for killing as many as 48 elderly patients by injecting disinfectant into their intravenous drips.

Suspicions began after an autopsy showed two elderly patients had been poisoned in Oguchi Hospital, Yokohama.

Sozo Nishikawa and Nobuo Yamaki, both 88, died on 18 and 20 September respectively after having a drip administered.

Investigators found 10 unused intravenous drip bags with small holes in their rubber seals on the fourth floor of the hospital, where the two elderly patients had died, The Japan Times reports.

Police believe the suspect may be an insider with medical knowledge.

They are now also investigating the deaths of 46 elderly patients since July, who were being treated on the same floor as the two deceased men.

Hospital staff told the newspaper there had been no outbreaks of infection which could account for the deaths.

The two patients died around a lightly staffed three-day public holiday. The entrance to the hospital was locked and guarded at night.

Last month, a staff member's lips became blistered after they consumed a drink that may have been laced with bleach, The Japan Times said in another report.

It is unknown whether the incidents are related.

The investigation comes two months after the killing of 19 people at a facility for the disabled near Tokyo.</s>A MAN believed to be in his 80s has been taken to hospital after being hit by a car about 5.15am.

Paramedics were called to David Low Way, Coolum Beach, to reports a pedestrian and vehicle had collided.

The elderly man received soft tissue injuries and was taken to Nambour General Hospital.</s>More than a quarter of Japan's population is aged 65 and above, putting a strain on medical and nursing facilities, where long hours and low pay discourage workers, a problem the government has vowed to tackle.

September's deaths follow the stabbing deaths of 19 residents of a home for the disabled in July, and the indictment of a former worker of a nursing home for killing three residents by throwing them off a balcony.

Police have said autopsies showed poisoning as the cause of death of two 88-year-old male patients on Sept. 18 and 20. Media said the men died as they received intravenous drip injections on the fourth floor of a Yokohama hospital.

A task force has been set up to conduct an investigation, police in the Kanegawa prefecture, south of the capital, said in a statement on Sept. 23.

Police believe someone probably injected disinfectant into their drip feed bags, media said, adding that no arrest had been made, and police were checking if the deaths could be linked to others on the same floor.

Replying to a query from Reuters whether police had told the hospital of autopsy findings that a surfactant, widely used in disinfectant and cleaning products, was present in the bodies, Yuki Uehara, a lawyer for the hospital, said, "Yes".

He did not elaborate.

From July until Sept. 20, as many as 46 other patients died on the same floor, or an average of 18 a month. That outstrips the monthly average of eight deaths on that floor during the 12 months to June, Uehara said.

He added, however, that the number of seriously ill patients in the hospital had risen from April onwards, which could partially explain the increase in the number of deaths.

Japan's social security system is creaking as the numbers of old people grow. Health ministry data show that abuse of elderly patients by nursing facility workers rose 36 percent in the year ending March 2015, to hit a record of 300 cases.
Authorities arrest a Japanese man for killing as many as 48 elderly patients at the Oguchi Hospital in Yokohama.