VIENNA -- Dr. Heinrich Gross, a psychiatrist who worked at a clinic where the Nazis killed and conducted cruel experiments on thousands of children, died Dec. 15, his family announced yesterday. He was 90.
Dr. Gross, who was implicated in nine deaths as part of a Nazi plot to eliminate ''worthless lives," had escaped trial in March after a court ruled he suffered from severe dementia. No cause of death was given in a brief statement issued by his family.
Dr. Gross was a leading doctor in Vienna's infamous Am Spiegelgrund clinic. Historians and survivors of the clinic had accused him of killing or taking part in the clinic's experiments on thousands of children deemed by the Nazis to be physically, mentally, or otherwise unfit for Adolf Hitler's vision of a perfect world.
Dr. Gross, who proclaimed his innocence for decades, had insisted he was not present at the hospital at the time in the 1940s when most of the children were killed.
''I was always against euthanasia," he told the weekly magazine News in 2000. ''I never sped up anyone's death, nor did I assign anyone to do so."
He became a prominent neurologist after the war and was awarded the prestigious Austrian Honorary Cross for Science and Art in 1975, but was stripped of the medal in 2003.
He was put on trial three times, but all the cases were dismissed. In a trial in the 1950s, the case was thrown out because of legal technicalities. A second case in the 1980s was dismissed because the 30-year statute of limitations on manslaughter had expired.
A third trial in 2000, in which Dr. Gross was accused of complicity in the murder of nine handicapped children who died as the result of abuse, was suspended after a psychiatrist testified he was unfit for trial because of advanced dementia.
Immediately after the suspension, Dr. Gross gave lively interviews in a local coffeehouse.
Across Europe, 75,000 people, including 5,000 children, were killed by the Nazis for real or imagined mental, physical or social disabilities.
Hundreds of urns containing the remains of young Austrians were buried quietly in 2002 after having been used for medical research as recently as 1978.
In September, a new play about the Spiegelgrund clinic made its debut in Vienna, underscoring how far the country has come in confronting its World War II past.
It portrays Dr. Gross as an evil Nazi scientist who views his patients only as research objects. Bone-chilling laughter hangs omnipresent over the stage during the production, which shows children confined in straitjackets, held in tiny cage beds, and force-fed medication through funnels.
During a trial in 1998, German historian Mathias Dahl said his research showed that Dr. Gross published five articles between 1955 and 1965 based on research using the preserved brains of children killed because they were deemed handicapped or antisocial.