The nurse being accused of killing 97 people.

If he is found guilty on all counts, she will become one of the biggest serial killers in post-World War II Germany.

The nurse, identified only as Niels H. has been charged with deliberate behavior of cardiac crises in patients, in order to restore their “frustration”.

The charges are linked to two hospitals where he worked in Low Saxony, Germany, over a seven - year period.

During the trial, he has admitted that he committed 90 murders at the time of working in the Oldenburg and Delmenhorst hospitals, leading investigators to conduct toxicological examinations in dozens of other patients who died in hospitals.

62 of these murders reportedly occurred as he worked as a nurse in Delmenhorst between 2003 and 2005, while the remainder occurred during his employment in Olddenburg, between 1999 and 2002.

In three other cases that investigators were considered suspicious, tests did not produce sufficient evidence to add them to the loading sheet of charges, writes Arbres.info. Police, authorities are continuing investigation into case