A nurse from Germany confessed to killing 100 patients who were in his care at the beginning of his murder trial on Oct. 30. 

Niels Högel, who is already serving a life sentence for killing two patients, confessed to 100 more as his trial began in the city of Oldenberg. Högel is charged with carrying out 100 murders between February 2000 and June 2005 across two German hospitals in the cities of Oldenberg and Delmenhorst. 

Högel​​​​​​​ allegedly administered lethal doses of drugs to patients so that he could impress his coworkers by reviving them. Högel​​​​​​​ was caught intentionally overdosing a patient by a fellow nurse in 2005. The age range of the many people he killed runs from 34 to 96. If Högel is found to have killed all 100 of the victims, he will go down as Germany's most-prolific serial killer since World War II.

Högel​​​​​​​ has been in jail since 2008, when he was convicted of attempted murder in relation to the case where he was caught administering the drugs. In 2015, he was convicted of killing two patients by lethal injection and confessed to a therapist of killing at least 30 more. Officials exhumed 130 bodies of patients who died while in Högel's care and tested their remains for signs that they had been murdered. 

Because of the sheer number of plaintiffs in the case, the trial had to be moved from the city's courthouse to a nearby festival hall.      

"We fought for four years for this trial and expect Högel is sentenced for another 100 murders," Christian Marbach, whose grandfather was killed by Högel, told the BBC.

When asked if he was guilty of the charges against him, Högel responded affirmatively, saying that he killed "more or less" all of the 100 patients.