Jack Kevorkian has died at a Detroit-area hospital.    The assisted suicide doctor was 83.

A spokesman for William Beaumont Hospital in Michigan confirms Kevorkian has died. He was being treated for heart and kidney problems, according to the Detroit Free Press. Longtime Kevorkian attorney Mayer Morganroth told the paper it appears Kevorkian suffered a pulmonary thrombosis when a blood clot from his leg broke free and lodged in his heart. "It was peaceful, he didn't feel a thing," Morganroth told the newspaper.  The retired pathologist claimed to have assisted in at least 130 suicides by allowing patients to administer fatal chemicals through a machine he called the Thanatron.   In 1999, Kevorkian was convicted of second-degree murder and the illegal delivery of a controlled substance, and was sentenced to 25 years in prison.  After eight years and numerous failed appeals, he was released from prison on good behavior.