CHICAGO (WBBM) — The Cook County Medical Examiner says the death of Sun-Times owner James Tyree was an accident.

The examiner’s report out Friday says an autopsy on Tyree–who was 53 and suffered from several health problems– found that he died of an air embolism following a dialysis catheter removal.

LISTEN: Newsradio 780’s Bob Roberts reports

Dr. Mark Yoder of Rush University Medical Center explained that a large air embolism can block blood from flowing to vital organs or the brain, causing a swift death.

The medical examiner also listed pneumonia and cancer of the stomach as secondary causes, but ruled his death an accident.

Tyree announced in October that he had cancer and would undergo chemotherapy. Tyree also suffered from diabetes and had kidney and pancreas transplants in 2006.

Tyree orchestrated the purchase of the Sun-Times and it suburban papers in 2009, saving the company from extinction. Tyree also held up a top position with Mesirow Financial. He had been chairman and chief executive officer since 1994 and had been with the company for more than 30 years.

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