Assisted suicide advocate Jack Kevorkian, who helped more than 130 people end their lives, has died at the age of 83.
Dr Kevorkian died at William Beaumont Hospital in Royal Oak in the Detroit-area. He was admitted to hospital with kidney and respiratory problems several weeks ago.
An official cause of death had not been determined, but his lawyer said it was likely to be pulmonary thrombosis.
By his own estimate, Dr Kevorkian helped 130 patients kill themselves with his self-built "suicide machines," sometimes inside his dilapidated 1968 Volkswagen van.
The retired pathologist usually dropped the corpses off at hospital emergency rooms and morgues, or left them in motel rooms.
He was convicted of murder in 1999 in the death of Thomas Youk, 52, a Michigan man suffering from amyotrophic lateral sclerosis, or Lou Gehrig's disease. He injected Youk with lethal drugs and then showed a videotape of the death on the CBS News television program "60 Minutes."
Sentenced to 10 to 25 years in prison in 1999, he was paroled in June 2007 after serving eight years. Dr Kevorkian's medical career was unconventional from the start. As an intern in the mid-1950s, he began photographing the eyes of patients at the moment of death, a practice that led his hospital colleagues to give him his nickname.
He later gained notoriety for advocating unorthodox medical practices such as live operations on death-row prisoners and blood transfusions from corpses to living patients.
By the time of his release from prison, most assisted-suicide advocates had distanced themselves from Dr Kevorkian, even though they credited him with raising public awareness of a previously taboo subject.
In the US, Oregon, Washington and Montana now allow some form of physician-assisted suicide, or what proponents call "death with dignity."
Murad "Jack" Kevorkian was born on May 28, 1928, in Pontiac, Michigan, the son of Armenian immigrants. His mother and father had escaped the massacre of Armenians by the Ottoman Turks in 1915.
Dr Kevorkian enrolled at the University of Michigan and then the university's medical school. He graduated in 1952 with a specialty in pathology, the study of disease.
A turning point in Kevorkian's life came as an intern at Henry Ford Hospital in Detroit. He came upon a middle-age woman who was suffering from cancer. In his 1991 book, Prescription: Medicine -- The Goodness of Planned Death, Dr Kevorkian described the patient as an "emaciated skeleton" with "yellow eyeballs sunken in their atrophic sockets."
"It seemed as though she was pleading for help and death at the same time," Dr Kevorkian wrote. "Out of sheer empathy alone, I could have helped her die with satisfaction."
"From that moment on, I was sure that doctor-assisted euthanasia and suicide are and always were ethical, no matter what anyone says or thinks."
Nicknamed "Dr. Death" for his study of dying as a young doctor and for aiding in suicides in the 1990s, Dr Kevorkian was also a painter and instrumentalist.
A CD entitled 'AVery Still Life' was released in 1997 and featured Dr. Kevorkian playing the organ and flute.