CHICAGO (AP) -- Tom Buchanan never really said what happened back in the 1940s when he was shot, but whatever it was, it finally killed him.

On Thursday, Cook County Medical Examiner's office spokesman Frank Shuftan said the weekend death of the 87-year-old retired steel worker has been ruled a homicide after an autopsy revealed that the "gunshot ultimately caused the complications to his abdomen that ultimately killed him."

Shuftan said family members didn't have any details about the shooting. "We don't know anything about it," he said.

Downtown Chicago Thursday morning. (AP Photo/Kiichiro Sato)

Buchanan's 82-year-old cousin, Mattie Matthews, said he never served in the military, so he could not have been shot in the World War II. She said Buchanan, a quiet man who never married or had any children, died without telling her what happened - even though she was probably the closest relative and friend that he had. All she knew about the shooting came from a conversation she overheard among grown-ups when she was a child.

"I was about 10 or 12 years old when I heard my aunt and my mother talking about how he had gotten shot but I never heard anything else and he (Buchanan) never talked about it to me," she said of the shooting that must have happened not long after Buchanan and his mother moved from Mississippi to Chicago.

Matthews said she recalled that conversation last week when Buchanan started talking about a pain in his gut. She said her cousin was the kind of man who didn't want anybody to make a fuss, and initially wouldn't even consider leaving the independent living facility on the city's South Side to see a doctor.

"But when I went Saturday he was holding his stomach and I told him I was taking him to the hospital because he was getting worse."

At 11:18 a.m. the next day, Buchanan was pronounced dead at Mercy Hospital and Medical Center, according to the medical examiner's office.

Matthews said she is saddened and confused by the death of her cousin who always seemed so healthy.

"Two weeks ago I was talking and I told him I wish I could get around like him," she said. "How could a gunshot wound he got 70 years ago... have contributed to his death?"

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