Over six years, he injected patients with drugs to cause cardiac arrest 'out of boredom' and to show his skill
Niels Hoegel: Killer nurse admits to murdering 100 patients
Former nurse Niels Hoegel is already serving a life sentence for murder, but on Tuesday he appeared in court pleading guilty to killing a further 100 people.
Between 1999 and 2005, Hoegel was working as a nurse at Oldenburg and Delmenhorst hospitals in northwestern Germany and was sentenced in 2015 for killing people in his care.
During that trial, he said he intentionally brought about cardiac crises in some 90 patients in Delmenhorst because he enjoyed the feeling of being able to resuscitate them. He rarely managed the feat. He later told investigators that he also killed patients in Oldenburg.
However, authorities believed that there may have been upwards of 100 victims and that the failure by the hospitals employing him may have allowed him to continue to kill.
On Tuesday Mr Hoegel plead guilty to committing the murders.
As the proceedings opened in the northern city of Oldenburg, presiding judge Sebastian Buehrmann asked whether the charges against him were accurate. Hoegel replied "yes".
"What I have admitted took place," he told the courtroom crowded with dozens of grieving relatives.
Who is Niels Hoegel?
Born December 30, 1976, in the North Sea coastal town of Wilhelmshaven, Hoegel became a nurse, like his father, at the age of 19.
In 1999 he took a job at the main hospital in Oldenburg and transferred to a facility in neighbouring Delmenhorst in 2003.
Former colleagues described him as diligent and likeable but began to take notice of a "troubling" number of deaths in the intensive care unit on his watch.
Between 2000 and 2005, he allegedly injected an overdose of medication in dozens of ailing, often aged patients with the aim of rescuing them from the brink of death.
He was rarely successful and in 2005 was caught in the act.
Psychiatrists who have evaluated Hoegel, the father of an adolescent daughter, say he has a severe narcissistic disorder.
Hoegel has admitted to killing around 30 of his patients and will face trial over 100 deaths.
But investigators say the actual toll of his deadly game with human life could top 200, though the true number may never be known because several presumed victims' bodies were cremated before they could be autopsied.
Hoegel brought on a premature death for his ailing patients to show off his "talents" to his increasingly suspicious colleagues, and out of "boredom", he has testified.
"I cannot imagine that he remembers each of the people [he killed]," said Petra Klein, who runs the crime victims' support group Weisser Ring in Oldenburg.
"It's all so treacherous."
Failure to investigate
The hospital in Oldenburg dismissed Hoegel in late 2002 due to mounting suspicions about the deaths of patients on his watch.
However, it failed to open an investigation, and even offered Hoegel a glowing professional recommendation, perhaps to ensure his quick departure.
"Without the mistakes of some people in Oldenburg... this series of murders by Niels Hoegel could have been stopped," said Christian Marbach, whose grandfather was one of the victims in Delmenhorst.
Colleagues and superiors at the two clinics will be asked to testify in the latest trial, as will Hoegel himself.
Marbach is hopeful he will "reveal everything" from the dock.
The suspected scale of his killing
A police file based on statistics provided by the Delmenhorst hospital shows that between 2003 and 2004 the death rate was twice as high as in previous years.
During the same period, the use of medication for cardiac ailments soared.
And in most cases when a patient died, Niels Hoegel was on duty.
The figures paint a damning picture but prosecutors only took action in 2008, ordering the exhumation of eight bodies under pressure from relatives of alleged victims.