Nurse Niels Hogell admitted he had intentionally induced cardia arrest in 90 of his patients by administering overdoses of heart medication. He said he enjoyed trying to revive his patients, but sometimes failed
Former nurse Niels Hoegel, accused in the murder of 97 patients, covers his face in this file photograph. (AP)
A German nurse serving a life sentence for two murders has been charged with killing 97 additional patients, prosecutors said Monday.
The new indictment against Niels Hoegel was expected after officials said in November he may have killed more than 100 patients in total.
Hoegel, who worked at a clinic in Oldenburg from 1999 to 2002 and in Delmenhorst from 2003 to 2005, was convicted of two murders and two attempted murders in 2015.
During his trial, Hoegel said he intentionally brought about cardiac crises in about 90 patients in Delmenhorst because he enjoyed the feeling of being able to resuscitate them.
Those statements prompted investigators to carry out toxicological examinations on dozens of other patients who died at the hospitals, which led to new charges.
t wasn't immediately clear when a new trial at the state court in Oldenburg might start. Additional convictions could affect Hoegel's possibility of parole, but there are no consecutive sentences in Germany.
Of the new cases, 62 involve patients who died in Delmenhorst and 35 patients in Oldenburg. Prosecutor Martin Koziolek said that, in three further cases investigators viewed as suspicious, tests didn't produce enough evidence to add them to the charge sheet.
Hoegel used a variety of drugs in his resuscitation attempts, Koziolek said. He added that prosecutors believe Hoegel "in all cases at least accepted the death of the patients as a result of the effect of the drugs."
As part of a wider investigation involving both hospitals, police and prosecutors reviewed more than 500 patient files and hundreds more hospital records. They also exhumed 134 bodies from 67 cemeteries, and questioned Hoegel six times.
Hoegel could have been stopped earlier if local health officials hadn't hesitated in alerting authorities, police said.
Criminal cases against former staff at the medical facilities are also being pursued.
The Associated Press contributed to this report.
Canadian nurse Elizabeth Mae Wettlaufer is accused of poisoning residents sho ranged in age from 75 to 90 in two Ontario facilities, the Ontario Provicial Police said at a news conference
Shocking selfies have emerged of a nurse, who allegedly murdered dozens of patients, posing with her thumbs up beside an apparently dead woman.
Italian nurse Daniela Poggiali, from the town of Lugo, in the Emilia-Romagna Region of central Italy, was arrested last month in connection with 38 deaths on her watch, some of which were described by prosecutors as 'very suspicious.'
Kimberly Saenz, a 38-year-old nurse who worked at the clinic, was set to face trial for one count of capital murder that accuses her of killing as many as five patients and five counts of aggravated assault for injuring five others.
Coming soon Behind the Murder Curtain the story of medical serial killers throughout the world and how they are identified and prosecuted