DETROIT (Reuters) - Assisted suicide advocate Jack Kevorkian, known as “Dr. Death” for helping more than 100 people end their lives, died early on Friday at age 83, his lawyer said.

Kevorkian died at Beaumont Hospital in Royal Oak, Michigan, where he had been hospitalized for about two weeks with kidney and heart problems, said Mayer Morganroth, Kevorkian’s attorney and friend.

The Detroit Free Press reported that Kevorkian, previously diagnosed with liver cancer, died from a blood clot that lodged in his heart.

Kevorkian, a pathologist, was focused on death and dying long before he ignited a polarizing national debate over assisted suicide by crisscrossing Michigan in a rusty Volkswagen van hauling a machine to help sick and suffering people end their lives.

Some viewed him as a hero who allowed the terminally ill to die with dignity, while his harshest critics reviled him as a cold-blooded killer who preyed on those suffering from chronic pain and depression. Most of his clients were middle-aged women.

“Dr. Jack Kevorkian was a rare human being,” his longtime attorney Geoffrey Fieger told reporters on Friday. “It’s a rare human being who can single-handedly take on an entire society by the scruff of its neck and force it to focus on the suffering of other human beings.”

Kevorkian launched his assisted-suicide campaign in 1990, allowing an Alzheimer’s patient to kill herself using a machine he devised that allowed her to trigger a lethal drug injection. He was charged with first-degree murder in the case, but the charges were later dismissed.

Fiery and unwavering in his cause, Kevorkian made a point of thumbing his nose at lawmakers, prosecutors and judges as he accelerated his campaign through the 1990s, using various methods including carbon monoxide gas. Often, Kevorkian would drop off bodies at hospitals late at night or leave them in motel rooms where the assisted suicides took place.

He beat Michigan prosecutors four times before his conviction for second-degree murder in 1999 after a CBS News program aired a video of Kevorkian administering lethal drugs to a 52-year-old man suffering from debilitating amyotrophic lateral sclerosis, or Lou Gehrig’s disease.

STILL IN PUBLIC EYE

Kevorkian was imprisoned for eight years. As a condition of his parole in 2007, he promised not to assist in any more suicides.

He himself had appealed to leave prison early because of poor health, but said he did not consider himself a candidate for assisted suicide.

Kevorkian did not leave the public eye after his exit from prison, giving occasional lectures and in 2008 running for Congress unsuccessfully.

Dr. Jack Kevorkian poses at the 62nd annual Primetime Emmy Awards in Los Angeles, California August 29, 2010. REUTERS/Mario Anzuoni

An HBO documentary on his life and a movie, “You Don’t Know Jack,” starring Al Pacino, brought him back into the limelight last year.

Born in the Detroit suburb of Pontiac, Kevorkian taught himself the flute and was a painter. Well read in philosophy and history, he cited Aristotle, Sir Thomas More and Pliny the Elder in his arguments for why people should have the right to die with dignity.

In a June 2010 interview with Reuters Television, the right-to-die activist said he was afraid of death as much as anyone else and said the world had a hypocritical attitude toward voluntary euthanasia, or assisted suicide.

“If we can aid people into coming into the world, why can’t we aid them in exiting the world?” he said.

Doctor-assisted suicide essentially became law in Oregon in 1997 and in Washington state in 2009. The practice of doctors writing prescriptions to help terminally ill patients kill themselves was ultimately upheld as legal by the U.S. Supreme Court.

Kevorkian was first dubbed “Dr. Death” by colleagues during his medical residency in the 1950s when he asked to work the night shift at Detroit Receiving Hospital so he could be on duty when more people died.

His career was interrupted by the Korean War, when he served 15 months as an Army medical officer.

After the U.S. Supreme Court permitted states to reinstate the death penalty in 1976, Kevorkian campaigned for performing medical experiments and harvesting the organs of death row inmates -- with their consent -- before their executions.